La Jolla Pharmaceutical Company Announces Initiation of Multicenter, Randomized, Phase 2 Clinical Study of LJPC-401 in Patients with Hereditary Hemochromatosis

SAN DIEGO, CA – December 18, 2017 – La Jolla Pharmaceutical Company (NASDAQ: LJPC) (the Company or La Jolla) today announced the initiation of LJ401-HH01, a Phase 2 clinical study of LJPC-401 (synthetic human hepcidin) in patients with hereditary hemochromatosis (HH). The most common genetic disease in Caucasians, HH is a disease characterized by a genetic mutation that results in a deficiency in the production of hepcidin, which is the body’s naturally occurring regulator of iron absorption and distribution. Without normal levels of hepcidin, excessive amounts of iron accumulate in the body. Symptoms of the disease include joint pain, abdominal pain, fatigue and weakness. If left untreated, HH can lead to liver cirrhosis, liver cancer, heart disease and/or failure and diabetes.

LJ401-HH01 is a multinational, multicenter, randomized, placebo-controlled, double-blind, Phase 2 study that is designed to evaluate the safety and efficacy of LJPC-401 as a treatment for HH. Approximately 60 patients will be randomized to receive weekly subcutaneous injections of either LJPC-401 or placebo for 12 weeks. The primary efficacy endpoint of the study is the change in transferrin saturation, a standard measurement of iron levels in the body and one of the two key measurements used to detect iron overload, from baseline to end of treatment. Secondary efficacy endpoints include: (i) the change in serum ferritin, the other key measurement used to detect iron overload, from baseline to end of treatment; and (ii) the requirement for and frequency of phlebotomy procedures during the study.

“There is a major need for new treatment modalities that improve the quality of life of the many patients suffering from hereditary hemochromatosis,” stated Jeff Vacirca, M.D., Chief of Clinical Research at New York Cancer & Blood Specialists and investigator in the study. “I am excited to be included in the clinical evaluation of a treatment that harnesses the body’s natural mechanism for iron regulation in a patient-friendly treatment regimen that could potentially reduce or eliminate the need for phlebotomy procedures in these patients.”

“Following the results of Phase 1 clinical studies that demonstrated that the administration of LJPC-401 resulted in dose-dependent reductions in iron levels, we are pleased to initiate LJ401- HH01 to evaluate the therapeutic potential of LJPC-401 in the important patient population of hereditary hemochromatosis,” said George F. Tidmarsh, M.D., Ph.D., President and Chief Executive Officer of La Jolla. “With the recent initiation of LJ401-BT01, our pivotal study of LJPC-401 in beta thalassemia patients, LJPC-401 now is being evaluated in two, multicenter, randomized, controlled clinical studies. These studies are important components of our overall development program for LJPC-401, which is aimed at helping the many patients suffering from the effects of iron overload due to a variety of underlying causes.”

The current standard treatment for HH is a blood removal procedure known as phlebotomy. Each phlebotomy procedure, which is usually conducted at a hospital, medical office or blood center, typically involves the removal of approximately a pint of blood. The required frequency of procedures varies by patient, but often ranges from one to two times per week for an initial period after diagnosis and once every one to three months chronically. Since most of the body’s iron is stored in red blood cells, chronic removal of blood can effectively lower iron levels if a phlebotomy regimen is adhered to. However, phlebotomy procedures may cause and may be associated with pain, bruising and scarring at the venous puncture site, fatigue and dizziness during and following the procedure and disruption of daily activities. Furthermore, phlebotomy is not appropriate in patients with poor venous access, anemia or heart disease.

About LJPC-401

La Jolla is developing LJPC-401 (synthetic human hepcidin) for the potential treatment of iron overload, which occurs as a result of diseases such as hereditary hemochromatosis (HH), beta thalassemia, sickle cell disease (SCD) and myelodysplastic syndrome (MDS). Hepcidin, an endogenous peptide hormone, is the body’s naturally occurring regulator of iron absorption and distribution. In healthy individuals, hepcidin prevents excessive iron accumulation in vital organs, such as the liver and heart, where it can cause significant damage and even result in death. The European Medicines Agency (EMA) Committee for Orphan Medicinal Products (COMP) has designated LJPC-401 as an orphan medicinal product for the treatment of beta thalassemia intermedia and major and SCD.

In September 2016, La Jolla reported positive results from a Phase 1 study of LJPC-401 in patients at risk of iron overload suffering from hereditary hemochromatosis, thalassemia and SCD. Single, escalating doses of LJPC-401 were associated with a dose-dependent, statistically significant reduction in serum iron. LJPC-401 was well-tolerated with no dose-limiting toxicities. Injection-site reactions were the most commonly reported adverse event and were all mild or moderate in severity, self-limiting and fully resolved.

In December 2017, La Jolla announced the initiation of a pivotal, multinational, multicenter, randomized, controlled study of LJPC-401 in patients with transfusion-dependent beta thalassemia who, despite chelation therapy, have cardiac iron levels above normal. La Jolla had previously announced that it had reached agreement with the European Medicines Agency (EMA) on the design of this registration study of LJPC-401.

About Hereditary Hemochromatosis

Hereditary hemochromatosis (HH) is the most common genetic disease in Caucasians. HH is a disease characterized by a genetic mutation that results in a deficiency in the production of hepcidin, which is the body’s naturally occurring regulator of iron absorption and distribution. Without normal levels of hepcidin, excessive amounts of iron accumulate in the body. Symptoms of the disease include joint pain, abdominal pain, fatigue and weakness. If left untreated, HH can lead to liver cirrhosis, liver cancer, heart disease and/or failure and diabetes.

The current standard treatment for HH is a blood removal procedure known as phlebotomy. Each phlebotomy procedure, which is usually conducted at a hospital, medical office or blood center, typically involves the removal of approximately a pint of blood. The required frequency of procedures varies by patient, but often ranges from one to two times per week for an initial period after diagnosis and once every one to three months chronically. Since most of the body’s iron is stored in red blood cells, chronic removal of blood can effectively lower iron levels if a phlebotomy regimen is adhered to. However, phlebotomy procedures may cause and may be associated with pain, bruising and scarring at the venous puncture site, fatigue and dizziness during and following the procedure and disruption of daily activities. Furthermore, phlebotomy is not appropriate in patients with poor venous access, anemia or heart disease.

About La Jolla Pharmaceutical Company

La Jolla Pharmaceutical Company is a biopharmaceutical company focused on the discovery, development and commercialization of innovative therapies intended to significantly improve outcomes in patients suffering from life-threatening diseases. The Company has several product candidates in development. LJPC-501 (synthetic human angiotensin II) is being developed for the potential treatment of hypotension in adult patients with distributive or vasodilatory shock who remain hypotensive despite fluid and vasopressor therapy. LJPC-401 (synthetic human hepcidin) is being developed for the potential treatment of conditions characterized by iron overload, such as hereditary hemochromatosis, beta thalassemia, sickle cell disease and myelodysplastic syndrome. For more information on La Jolla, please visit www.ljpc.com.

Forward Looking Statement Safe Harbor

This press release contains forward-looking statements as that term is defined in the Private Securities Litigation Reform Act of 1995. These statements relate to future events or the Company’s future results of operations. These statements are only predictions or statements of current expectations and involve known and unknown risks, uncertainties and other factors, that may cause actual results to be materially different from those anticipated by the forward-looking statements. The Company cautions readers not to place undue reliance on any such forward- looking statements, which speak only as of the date they were made. Certain of these risks, uncertainties and other factors are described in greater detail in the Company’s filings with the U.S. Securities and Exchange Commission (SEC), all of which are available free of charge on the SEC’s website www.sec.gov. These risks include, but are not limited to, risks relating to: the timing, costs, conduct and outcome of clinical studies; the anticipated treatment of future clinical data by the FDA, the EMA or other regulatory authorities, including whether such data will be sufficient for approval; the timing and prospects for approval of LJPC-501 or LJPC-401 by the FDA, the EMA or other regulatory authorities; risks relating to the scope of product labels (if approved); potential market sizes; the success of future development activities; potential indications for which the Company’s product candidates may be developed; the anticipated timing for regulatory actions; the impact of pharmaceutical industry regulation and healthcare legislation in the United States; and the success of future development activities. The Company expressly disclaims any intent to update any forward-looking statements to reflect the outcome of subsequent events.

Company Contacts

Sandra Vedrick

Associate Director, Investor Relations & Human Resources

La Jolla Pharmaceutical Company Phone: 858 207 4264 Ext: 1135 Email: svedrick@ljpc.com

and

Dennis M. Mulroy

Chief Financial Officer

La Jolla Pharmaceutical Company Phone: 858 207 4264 Ext: 1040 Email: dmulroy@ljpc.com

GIAPREZA™ (angiotensin II) Significantly Improved Survival and Reduced Time on Renal Replacement Therapy in Patients with Acute Kidney Injury

Analyses to Be Presented in Oral and Poster Sessions at The 23rd International Conference on Advances in Critical Care Nephrology AKI & CRRT 2018

Manuscript Published Online in Critical Care Medicine

SAN DIEGO, March 06, 2018 (GLOBE NEWSWIRE) — La Jolla Pharmaceutical Company (Nasdaq:LJPC) today announced the release of data from analyses of the impact of GIAPREZA™ (angiotensin II) on outcomes of a subset of patients with acute kidney injury requiring renal replacement therapy (AKI-RRT) enrolled in the ATHOS-3 (Angiotensin II for the Treatment of High Output Shock) study.

The presentation, entitled “Outcomes in Patients with Acute Kidney Injury Receiving Angiotensin II for Vasodilatory Shock,” will take place during The 23rd International Conference on Advances in Critical Care Nephrology – AKI & CRRT 2018, being held March 6-9, 2018 in San Diego, California. The manuscript, entitled “Outcomes in patients with vasodilatory shock and renal replacement therapy treated with intravenous angiotensin II” was published online in Critical Care Medicine.

“Acute kidney injury requiring dialysis associated with distributive shock, also referred to as vasodilatory shock, represents a significant medical risk for patients and a significant financial burden to the health care system,” said James Tumlin M.D., Professor of Medicine and Director of NephroNet Clinical Trials Consortium. “These analyses of the effect of angiotensin II on AKI patients requiring dialysis in the ATHOS-3 study demonstrated angiotensin II is a promising therapy to address this unmet need.”

The presentations and manuscript detail the outcomes of patients with acute kidney injury (AKI) and vasodilatory shock enrolled in the ATHOS-3 study of GIAPREZA. In this post-hoc analysis, the data from 105 AKI patients (GIAPREZA n=45; placebo n=60) requiring renal replacement therapy (RRT) at study drug initiation were analyzed. Survival through day 28 was 53% (95% CI: 38%-67%) for the GIAPREZA group compared to 30% (95% CI: 19%-41%) for the placebo group (p = 0.012). By day 7, 38% (95% CI: 25%-54%) of patients treated with GIAPREZA discontinued RRT compared to 15% (95% CI: 8%-27%) of patients treated with placebo (p = 0.007). Mean arterial pressure (MAP) response at hour 3 was achieved in 53% (95% CI: 38%-68%) of patients treated with GIAPREZA compared to 22% (95% CI: 12%-34%) of patients treated with placebo (p = 0.001).

23rd International Conference on Advances in Critical Care Nephrology – AKI & CRRT 2018 Presentation Details
Presentation Title: Outcomes in Patients with Acute Kidney Injury Receiving Angiotensin II for Vasodilatory Shock
Presenter: James Tumlin, M.D., Professor of Medicine and Director of NephroNet Clinical Trials Consortium
Poster Presentation Date: Tuesday, March 6, 2018 5:30 pm – 7:00 pm and Wednesday, March 7, 2018 6:00 pm – 8:00 pm Pacific Time
Oral Presentation Date: Friday, March 9, 2018 11:00 am – 12:25 pm Pacific Time
Location: Manchester Grand Hyatt, San Diego, CA

About GIAPREZA

In December 2017, GIAPREZA™ (angiotensin II) was approved by the U.S. Food and Drug Administration (FDA) to increase blood pressure in adults with septic or other distributive shock. GIAPREZA mimics the body’s endogenous regulatory peptide that is central to the renin-angiotensin-aldosterone system to increase blood pressure. Prescribing information for GIAPREZA is available at www.giapreza.com.

IMPORTANT SAFETY INFORMATION

Contraindications

None

Warnings and Precautions

There is a potential for venous and arterial thrombotic and thromboembolic events in patients who receive GIAPREZA. Use concurrent venous thromboembolism (VTE) prophylaxis.

Adverse Reactions

The most common adverse reactions reported in greater than 10% in GIAPREZA treated patients were thromboembolic events.

Drug Interactions

Angiotensin converting enzyme (ACE) inhibitors may increase response to GIAPREZA.
Angiotensin II receptor blockers (ARB) may reduce response to GIAPREZA.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch or call 1-800-FDA-1088.

For additional information, please see Full Prescribing Information.

About Shock and Septic or Other Distributive Shock

Over 1 million Americans are affected by shock on an annual basis, with 1 in 3 patients being treated for shock in the intensive care unit. Distributive shock is the most common type of shock in the inpatient setting with approximately 800,000 distributive shock cases in the United States per year. Of these cases, an estimated 90% are septic shock patients. Approximately 300,000 do not achieve adequate blood pressure response with standard of care vasopressor therapy (catecholamines and vasopressin). The inability to achieve or maintain adequate blood pressure results in inadequate blood flow to the body’s organs and tissue and is associated with a mortality rate exceeding most acute conditions requiring hospitalization.

About La Jolla Pharmaceutical Company

La Jolla Pharmaceutical Company is a biopharmaceutical company focused on the discovery, development and commercialization of innovative therapies intended to significantly improve outcomes in patients suffering from life-threatening diseases. GIAPREZA™ (angiotensin II), formerly known as LJPC-501, was approved by the U.S. Food and Drug Administration (FDA) on December 21, 2017 as a vasoconstrictor to increase blood pressure in adults with septic or other distributive shock. LJPC‑401 (synthetic human hepcidin), a clinical-stage investigational product, is being developed for the potential treatment of conditions characterized by iron overload, such as hereditary hemochromatosis, beta thalassemia, sickle cell disease and myelodysplastic syndrome. For more information, please visit www.ljpc.com.

Forward-looking Statements

This press release contains forward-looking statements, as that term is defined in the Private Securities Litigation Reform Act of 1995. These statements relate to expectations regarding future events or La Jolla’s future results of operations. These statements are only predictions or statements of current expectations and involve known and unknown risks, uncertainties and other factors that may cause actual results to be materially different from those anticipated by the forward-looking statements. La Jolla cautions readers not to place undue reliance on any such forward-looking statements, which speak only as of the date they were made. Certain of these risks, uncertainties and other factors are described in greater detail in La Jolla’s filings with the U.S. Securities and Exchange Commission (SEC), all of which are available free of charge on the SEC’s website www.sec.gov. These risks include, but are not limited to, risks relating to: unforeseen safety issues from the administration of GIAPREZA in patients; the anticipated treatment of future clinical data by the FDA, the EMA or other regulatory authorities; potential market sizes, including for septic or other distributive shock; our ability to successfully commercialize, market and achieve market acceptance of GIAPREZA; and other risks and uncertainties identified in our filings with the SEC. La Jolla expressly disclaims any intent to update any forward‑looking statements to reflect the outcome of subsequent events.

Company Contacts

Sandra Vedrick
Director, Investor Relations & Human Resources
La Jolla Pharmaceutical Company
Phone: (858) 207-4264 Ext: 1135
Email: svedrick@ljpc.com

and

Dennis M. Mulroy
Chief Financial Officer
La Jolla Pharmaceutical Company
Phone: (858) 207-4264 Ext: 1040
Email: dmulroy@ljpc.com

GIAPREZA™ (angiotensin II) Significantly Improved Survival of Patients with High APACHE II Scores in ATHOS-3 Study

Analysis to Be Presented in Oral Session at the Society of Critical Care Medicine’s 47th Critical Care Congress
SAN DIEGO, Feb. 25, 2018 (GLOBE NEWSWIRE) — La Jolla Pharmaceutical Company (Nasdaq:LJPC) today announced that an abstract, entitled “Effect of Disease Severity on Survival in Patients Receiving Angiotensin II for Vasodilatory Shock,” will be presented at the Society of Critical Care Medicine’s (SCCM) 47th Critical Care Congress, being held from February 25 to 28, 2018 in San Antonio, Texas.

The abstract, which was published in the January Supplement of Critical Care Medicine and online, includes results from a pre-specified analysis from the ATHOS-3 (Angiotensin II for the Treatment of High Output Shock) Phase 3 study of GIAPREZATM (angiotensin II) in patients with high severity of illness, defined as an APACHE II (Acute Physiology and Chronic Health Evaluation II) score > 30 or baseline MAP < 65 mmHg, despite treatment with high-dose vasopressors. The authors present data showing a lower 28-day mortality rate in patients with baseline APACHE II scores > 30 in the GIAPREZA group versus the placebo group: 28-day mortality was 51.8% (n = 58) for the GIAPREZA group compared to 70.8% (n = 65) for the placebo group (hazard ratio=0.62 [95% CI: 0.39, 0.98; p=0.037]). In patients with a baseline MAP < 65 mmHg, a trend towards improved 28-day mortality was seen in the GIAPREZA group compared to the placebo group: 28-day mortality was 54.2% (n = 52) for the GIAPREZA group compared to 70.4% (n = 50) for the placebo group (hazard ratio=0.66 [95% CI: 0.40, 1.09; p=0.10]).

Society of Critical Care Medicine’s 47th Critical Care Congress Presentation Details

Star Research Presentation: Sepsis and Shock
Presentation Number:  6
Presentation Title: Effect of Disease Severity on Survival in Patients Receiving Angiotensin II for Vasodilatory Shock
Presenter: Azra Bihorac, M.D., R. Glenn Davis Associate Professor of Medicine, Surgery and Anesthesiology, University of Florida
Session Date: Sunday, February 25, 2018
Session Time: 3:45 pm – 5:45 pm Central Time
Session Room: Henry B. Gonzalez Convention Center, Hemisfair Ballroom C1

About GIAPREZA

In December 2017, GIAPREZA™ (angiotensin II) was approved by the U.S. Food and Drug Administration (FDA) to increase blood pressure in adults with septic or other distributive shock. GIAPREZA mimics the body’s endogenous regulatory peptide that is central to the renin-angiotensin-aldosterone system to increase blood pressure. In the ATHOS-3 Phase 3 study, the primary endpoint of: (i) a mean arterial pressure (MAP) increase of ≥ 10 mmHg; or (ii) a MAP of ≥ 75 mmHg, was achieved by 70% of patients randomized to GIAPREZA, compared to 23% of patients randomized to placebo (p < 0.0001); both arms were treated with standard-of-care vasopressors. The recommended starting dosage of GIAPREZA is 20 nanograms (ng)/kg/min via continuous intravenous infusion. Close monitoring during the first 5 minutes of GIAPREZA initiation is recommended. GIAPREZA is available in 1 mL single dose vials, each containing 2.5 mg of angiotensin II (as a sterile liquid). Prescribing information for GIAPREZA is available at www.giapreza.com.

IMPORTANT SAFETY INFORMATION

Warnings and Precautions

The safety of GIAPREZA was evaluated in 321 adults with septic or other distributive shock in the randomized, double-blind, placebo-controlled ATHOS-3 Phase 3 study. There was a higher incidence of venous and arterial thrombotic and thromboembolic events in patients who received GIAPREZA compared to placebo-treated patients in the ATHOS-3 study [13% (21/163 patients) vs. 5% (8/158 patients)]. The major imbalance was in deep venous thromboses. Use concurrent venous thromboembolism prophylaxis.

Adverse Reactions

Adverse reactions that occurred in ≥4% of patients treated with GIAPREZA and ≥1.5% more often than placebo-treated patients in the ATHOS-3 study were thromboembolic events (including deep vein thrombosis), thrombocytopenia, tachycardia, fungal infection, delirium, acidosis, hyperglycemia and peripheral ischemia.

Drug Interactions

Angiotensin converting enzyme (ACE) inhibitors may increase response to GIAPREZA.
Angiotensin II receptor blockers (ARB) may reduce response to GIAPREZA.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch or call 1-800-FDA-1088.

For additional information, please see Full Prescribing Information.

About La Jolla Pharmaceutical Company

La Jolla Pharmaceutical Company is a biopharmaceutical company focused on the discovery, development and commercialization of innovative therapies intended to significantly improve outcomes in patients suffering from life-threatening diseases. GIAPREZA™ (angiotensin II), formerly known as LJPC-501, was approved by the U.S. Food and Drug Administration (FDA) on December 21, 2017 as a vasoconstrictor to increase blood pressure in adults with septic or other distributive shock. LJPC‑401 (synthetic human hepcidin), a clinical-stage investigational product, is being developed for the potential treatment of conditions characterized by iron overload, such as hereditary hemochromatosis, beta thalassemia, sickle cell disease and myelodysplastic syndrome. For more information, please visit www.ljpc.com.

Forward-looking Statements

This press release contains forward-looking statements, as that term is defined in the Private Securities Litigation Reform Act of 1995. These statements relate to expectations regarding future events or La Jolla’s future results of operations. These statements are only predictions or statements of current expectations and involve known and unknown risks, uncertainties and other factors that may cause actual results to be materially different from those anticipated by the forward-looking statements. La Jolla cautions readers not to place undue reliance on any such forward-looking statements, which speak only as of the date they were made. Certain of these risks, uncertainties and other factors are described in greater detail in La Jolla’s filings with the U.S. Securities and Exchange Commission (SEC), all of which are available free of charge on the SEC’s website www.sec.gov. These risks include, but are not limited to, risks relating to: clinical studies with GIAPREZA may not be successful in evaluating their safety and tolerability or providing evidence of efficacy; unforeseen safety issues from the administration of GIAPREZA in patients; the anticipated treatment of future clinical data by the FDA, the EMA or other regulatory authorities; potential market sizes, including for septic or other distributive shock; our ability to successfully commercialize, market and achieve market acceptance of GIAPREZA; and other risks and uncertainties identified in our filings with the SEC. La Jolla expressly disclaims any intent to update any forward‑looking statements to reflect the outcome of subsequent events.

Company Contacts

Sandra Vedrick
Director, Investor Relations & Human Resources
La Jolla Pharmaceutical Company
Phone: (858) 207-4264 Ext: 1135
Email: svedrick@ljpc.com

and

Dennis M. Mulroy
Chief Financial Officer
La Jolla Pharmaceutical Company
Phone: (858) 207-4264 Ext: 1040
Email: dmulroy@ljpc.com

La Jolla Pharmaceutical Company Announces Financial Results for the Three and Twelve Months Ended December 31, 2017 and Recent Corporate Progress

SAN DIEGO, Calif., Feb. 22, 2018 (GLOBE NEWSWIRE) — La Jolla Pharmaceutical Company (Nasdaq:LJPC), a leader in the development of innovative therapies intended to significantly improve outcomes in patients suffering from life-threatening diseases, today announced financial results for the three and twelve months ended December 31, 2017 and highlighted recent corporate progress.

Recent Corporate Progress

  • In December 2017, GIAPREZA™ (angiotensin II), injection for intravenous infusion, formerly known as LJPC-501, was approved by the U.S. Food and Drug Administration (FDA) as a vasoconstrictor indicated to increase blood pressure in adults with septic or other distributive shock.
  • In December 2017, La Jolla announced the initiation of LJ401-HH01, a multinational, multicenter, randomized, placebo-controlled, double-blind, Phase 2 study that is designed to evaluate the safety and efficacy of LJPC-401 (synthetic human hepcidin) as a treatment for hereditary hemochromatosis (HH). Approximately 60 patients in 5 countries will be randomized to receive weekly subcutaneous injections of either LJPC-401 or placebo for 12 weeks. The primary efficacy endpoint of the study is the change in transferrin saturation, a standard measurement of iron levels in the body and one of the two key measurements used to detect iron overload, from baseline to end of treatment. Secondary efficacy endpoints include: (i) the change in serum ferritin, the other key measurement used to detect iron overload, from baseline to end of treatment; and (ii) the requirement for and frequency of phlebotomy procedures used during the study.
  • In December 2017, La Jolla announced the initiation of LJ401-BT01, a pivotal, multinational, multicenter, randomized, controlled study of LJPC-401 in patients with transfusion-dependent beta thalassemia who, despite chelation therapy, have cardiac iron levels above normal. Approximately 100 patients in 9 countries, including the U.S., will be randomized 1:1 to receive either: (i) weekly subcutaneous injections of LJPC-401, while continuing standard-of-care chelation therapy (LJPC-401 treatment arm); or (ii) a continuation of standard-of-care chelation therapy only (observation arm). After 6 months of treatment, patients randomized to the observation arm will cross over to receive LJPC-401 (plus standard-of-care chelation therapy) for 6 months, while patients randomized to the LJPC-401 treatment arm will continue with LJPC-401 (plus standard-of-care chelation therapy) for an additional 6 months (for a total of one year). The primary efficacy endpoint of this study is the change in iron content in the heart after 6 months, as measured by cardiac magnetic resonance imaging (MRI). If this study is successful, we would anticipate filing a market authorization application (MAA) for LJPC-401 in Europe.

“2017 was an exciting year for La Jolla, highlighted by the FDA’s approval of GIAPREZA,” said George Tidmarsh, M.D., Ph.D., La Jolla’s President and Chief Executive Officer. “We are excited to bring this new treatment option to the many critically ill patients suffering from septic or other distributive shock.”

Results of Operations

As of December 31, 2017, La Jolla had $90.9 million in cash and cash equivalents, compared to $65.7 as of December 31, 2016. La Jolla’s net cash used for operating activities for the twelve months ended December 31, 2017 was $84.9 million compared to net cash used for operating activities of $58.7 million for the same period in 2016. La Jolla’s net loss for the three and twelve months ended December 31, 2017 was $38.5 million and $114.8 million, or $1.74 per share and $5.41 per share, respectively, compared to a net loss of $24.9 million and $78.2 million, or $1.44 per share and $4.54 per share, respectively, for the same periods in 2016.

About GIAPREZA

In December 2017, GIAPREZA™ (angiotensin II) was approved by the U.S. Food and Drug Administration (FDA) to increase blood pressure in adults with septic or other distributive shock. GIAPREZA mimics the body’s endogenous regulatory peptide that is central to the renin-angiotensin-aldosterone system to increase blood pressure. In the ATHOS-3 Phase 3 study, the primary endpoint of: (i) a mean arterial pressure (MAP) increase of ≥ 10 mmHg; or (ii) a MAP of ≥ 75 mmHg, was achieved by 70% of patients randomized to GIAPREZA, compared to 23% of patients randomized to placebo (p < 0.0001); both arms were treated with standard-of-care vasopressors. The recommended starting dosage of GIAPREZA is 20 nanograms (ng)/kg/min via continuous intravenous infusion. Close monitoring during the first 5 minutes of GIAPREZA initiation is recommended. GIAPREZA is available in 1 mL single dose vials, each containing 2.5 mg of angiotensin II (as a sterile liquid). Prescribing information for GIAPREZA is available at www.giapreza.com.

IMPORTANT SAFETY INFORMATION

Warnings and Precautions

The safety of GIAPREZA was evaluated in 321 adults with septic or other distributive shock in the randomized, double-blind, placebo-controlled Phase 3 study, ATHOS-3. There was a higher incidence of venous and arterial thrombotic and thromboembolic events in patients who received GIAPREZA compared to placebo-treated patients in the ATHOS-3 study [13% (21/163 patients) vs. 5% (8/158 patients)]. The major imbalance was in deep venous thromboses. Use concurrent venous thromboembolism prophylaxis.

Adverse Reactions

Adverse reactions that occurred in ≥4% of patients treated with GIAPREZA and ≥1.5% more often than placebo-treated patients in the ATHOS-3 study were thromboembolic events (including deep vein thrombosis), thrombocytopenia, tachycardia, fungal infection, delirium, acidosis, hyperglycemia and peripheral ischemia.

Drug Interactions

Angiotensin converting enzyme (ACE) inhibitors may increase response to GIAPREZA. Angiotensin II receptor blockers (ARB) may reduce response to GIAPREZA.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch or call 1-800-FDA-1088.

For additional information, please see Full Prescribing Information.

About La Jolla Pharmaceutical Company

La Jolla Pharmaceutical Company is a biopharmaceutical company focused on the discovery, development and commercialization of innovative therapies intended to significantly improve outcomes in patients suffering from life-threatening diseases. GIAPREZA™ (angiotensin II), formerly known as LJPC-501, was approved by the U.S. Food and Drug Administration (FDA) on December 21, 2017 as a vasoconstrictor to increase blood pressure in adults with septic or other distributive shock. LJPC‑401 (synthetic human hepcidin), a clinical-stage investigational product, is being developed for the potential treatment of conditions characterized by iron overload, such as hereditary hemochromatosis, beta thalassemia, sickle cell disease and myelodysplastic syndrome. For more information, please visit www.ljpc.com.

Forward-looking Statements

This press release contains forward-looking statements, as that term is defined in the Private Securities Litigation Reform Act of 1995. These statements relate to expectations regarding future events or La Jolla’s future results of operations. These statements are only predictions or statements of current expectations and involve known and unknown risks, uncertainties and other factors that may cause actual results to be materially different from those anticipated by the forward-looking statements. La Jolla cautions readers not to place undue reliance on any such forward-looking statements, which speak only as of the date they were made. Certain of these risks, uncertainties and other factors are described in greater detail in La Jolla’s filings with the U.S. Securities and Exchange Commission (SEC), all of which are available free of charge on the SEC’s website www.sec.gov. These risks include, but are not limited to, risks relating to: our ability to successfully commercialize, market and achieve market acceptance of GIAPREZA and other product candidates; potential market sizes, including for septic or other distributive shock; the success of development activities for LJPC-401 and other product candidates; and other risks and uncertainties identified in our filings with the SEC. Forward-looking statements are presented as of the date of this press release, and La Jolla expressly disclaims any intent to update any forward‑looking statements to reflect the outcome of subsequent events.

Company Contacts

Sandra Vedrick

Director, Investor Relations & Human Resources

La Jolla Pharmaceutical Company

Phone: 858 207 4264 Ext: 1135

Email: svedrick@ljpc.com

and

Dennis M. Mulroy

Chief Financial Officer

La Jolla Pharmaceutical Company

Phone: 858 207 4264 Ext: 1040

Email: dmulroy@ljpc.com

La Jolla Pharmaceutical Company Announces the Treatment of First Patient in GIAPREZA™ (angiotensin II) Pediatric Study

SAN DIEGO, Feb. 21, 2018 (GLOBE NEWSWIRE) — La Jolla Pharmaceutical Company (Nasdaq:LJPC) today announced that the first pediatric patient has been treated in LJ501-CRH02, La Jolla’s open-label study of GIAPREZATM (angiotensin II), injection for intravenous infusion, in pediatric patients (ages 2-17) with shock who remain hypotensive despite receiving fluid and current standard-of-care vasopressor therapy.

LJ501-CRH02 is an open-label study that will enroll approximately 30 patients in 10 pediatric intensive care units across the United States. The primary objective of this study is to evaluate the effect of GIAPREZA on mean arterial pressure (MAP) or total norepinephrine (NE)-equivalent dosing, two hours after the initiation of GIAPREZA.

“We are thrilled to enroll the first pediatric patient in this open-label study of angiotensin II in children with vasodilatory septic or other distributive shock,” said Dwight Bailey, D.O., Specialty Medical Director, Pediatric Critical Care Medicine Division, Atrium Health’s Levine Children’s Hospital in Charlotte, North Carolina. “The critical care team and the patient’s family were grateful to have another option for the treatment of this young patient who we believe was suffering from influenza, which was complicated by a bacterial superinfection and septic shock, especially given the limited therapeutic options for pediatric patients.”

In December 2017, GIAPREZA was approved by the U.S. Food and Drug Administration (FDA) to increase blood pressure in adults with septic or other distributive shock. GIAPREZA (angiotensin II) mimics the body’s endogenous regulatory peptide that is central to the renin-angiotensin-aldosterone system to increase blood pressure.

About Patients with Septic or Other Distributive Shock Failing Standard Therapy

Septic or other distributive shock (dangerously low blood pressure with adequate cardiac function) can become life threatening when a patient is unable to achieve target mean arterial pressure (MAP) despite adequate fluid resuscitation and treatment with other available vasopressors (catecholamines and/or vasopressin). Distributive shock is the most common type of shock in the inpatient setting. Shock is prevalent, affecting 1 in 3 intensive care unit patients. There are approximately 800,000 distributive shock cases in the United States each year. Of these cases, an estimated 90% are septic shock patients. Approximately 300,000 of these patients do not achieve adequate blood pressure response with fluids and typical, first-line catecholamine therapy. The inability to achieve or maintain adequate blood pressure results in inadequate blood flow to the body’s organs and tissue and is associated with organ damage and a mortality rate exceeding most acute conditions requiring hospitalization.

About GIAPREZA

In December 2017, GIAPREZATM (angiotensin II) was approved by the U.S. Food and Drug Administration (FDA) to increase blood pressure in adults with septic or other distributive shock. GIAPREZA (angiotensin II) mimics the body’s endogenous regulatory peptide that is central to the renin-angiotensin-aldosterone system to increase blood pressure. In the ATHOS-3 Phase 3 study, the primary endpoint of: (i) a mean arterial pressure (MAP) increase of ≥ 10 mmHg; or (ii) a MAP of ≥ 75 mmHg, was achieved by 70% of patients randomized to GIAPREZA, compared to 23% of patients randomized to placebo (p < 0.0001); both arms were treated with standard-of-care vasopressors. The recommended starting dosage of GIAPREZA is 20 nanograms (ng)/kg/min via continuous intravenous infusion. Close monitoring during the first 5 minutes of GIAPREZA initiation is recommended. GIAPREZA is available as a carton of 1 mL single dose vials, each containing 2 mg of angiotensin II (as a sterile liquid). Prescribing information for GIAPREZA is available at www.giapreza.com.

IMPORTANT SAFETY INFORMATION

Warnings and Precautions

The safety of GIAPREZA was evaluated in 321 adults with septic or other distributive shock in the randomized, double-blind, placebo-controlled ATHOS-3 Phase 3 study. There was a higher incidence of venous and arterial thromboembolic events in patients who received GIAPREZA compared to placebo-treated patients in the Phase 3 study [13% (21/163 patients) vs. 5% (8/158 patients)]. The major imbalance was in venous thrombosis. Use concurrent venous thromboembolism prophylaxis.

Adverse Reactions

Adverse reactions that occurred in ≥4% of patients treated with GIAPREZA and ≥1.5% more often than placebo-treated patients in the ATHOS-3 study were thromboembolic events (including deep vein thrombosis), thrombocytopenia, tachycardia, fungal infection, delirium, acidosis, hyperglycemia and peripheral ischemia.

Drug Interactions

Angiotensin converting enzyme (ACE) inhibitors may increase response to GIAPREZA.
Angiotensin II receptor blockers (ARB) may reduce response to GIAPREZA.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch or call 1-800-FDA-1088.

For additional information, please see Full Prescribing Information.

About La Jolla Pharmaceutical Company

La Jolla Pharmaceutical Company is a biopharmaceutical company focused on the discovery, development and commercialization of innovative therapies intended to significantly improve outcomes in patients suffering from life-threatening diseases. GIAPREZATM (angiotensin II), formerly known as LJPC-501, was approved by the U.S. Food and Drug Administration (FDA) on December 21, 2017 as a vasoconstrictor to increase blood pressure in adults with septic or other distributive shock. LJPC 401 (synthetic human hepcidin), a clinical-stage investigational product, is being developed for the potential treatment of conditions characterized by iron overload, such as hereditary hemochromatosis, beta thalassemia, sickle cell disease and myelodysplastic syndrome. For more information on La Jolla, please visit www.ljpc.com.

Forward-looking Statements

This press release contains forward-looking statements, as that term is defined in the Private Securities Litigation Reform Act of 1995. These statements relate to expectations regarding future events or La Jolla’s future results of operations. These statements are only predictions or statements of current expectations and involve known and unknown risks, uncertainties and other factors that may cause actual results to be materially different from those anticipated by the forward-looking statements. La Jolla cautions readers not to place undue reliance on any such forward-looking statements, which speak only as of the date they were made. Certain of these risks, uncertainties and other factors are described in greater detail in La Jolla’s filings with the U.S. Securities and Exchange Commission (SEC), all of which are available free of charge on the SEC’s website www.sec.gov. These risks include, but are not limited to, risks relating to: clinical studies with GIAPREZA may not be successful in evaluating their safety and tolerability or providing evidence of efficacy; unforeseen safety issues from the administration of GIAPREZA in patients; the anticipated treatment of future clinical data by the FDA, the EMA or other regulatory authorities; potential market sizes, including for septic or other distributive shock; our ability to successfully commercialize, market and achieve market acceptance of GIAPREZA; and other risks and uncertainties identified in our filings with the SEC. La Jolla expressly disclaims any intent to update any forward‑looking statements to reflect the outcome of subsequent events.

Company Contacts

Sandra Vedrick
Director, Investor Relations & Human Resources
La Jolla Pharmaceutical Company
Phone: (858) 207-4264 Ext: 1135
Email: svedrick@ljpc.com

and

Dennis M. Mulroy
Chief Financial Officer
La Jolla Pharmaceutical Company
Phone: (858) 207-4264 Ext: 1040
Email: dmulroy@ljpc.com

La Jolla Pharmaceutical Company Announces FDA Approval of Giapreza™ (angiotensin II)

Giapreza increases blood pressure in adults with septic or other distributive shock

La Jolla to host conference call and webcast at 8:30 a.m. EST on December 22, 2017

SAN DIEGO, Dec. 21, 2017 (GLOBE NEWSWIRE) — La Jolla Pharmaceutical Company (Nasdaq:LJPC) (the Company or La Jolla) today announced that the U.S. Food and Drug Administration (FDA) has approved GiaprezaTM (angiotensin II) to increase blood pressure in adults with septic or other distributive shock.

“We appreciate FDA’s rapid review and approval of Giapreza and are especially grateful to the patients, families and dedicated critical care teams who made the development of Giapreza possible,” said George F. Tidmarsh, M.D., Ph.D., President and Chief Executive Officer of La Jolla. “We look forward to bringing this new treatment option to the many critically ill patients suffering from septic or other distributive shock.”

“Vasopressors are critical to treat patients with shock. The critical care community now has another tool to use,” said John A. Kellum, M.D., Director of Center for Critical Care Nephrology, Vice Chair for Research, and Professor of Critical Care Medicine, University of Pittsburgh. “The approval of angiotensin II represents a major advance in the treatment of patients with septic or distributive shock.”

La Jolla plans to make Giapreza available for patients in the U.S. in March 2018. Prescribing information for Giapreza is available at www.giapreza.com.

About Septic or Other Distributive Shock

Distributive shock is the most common type of shock in the inpatient setting, affecting approximately one-third of intensive care unit patients. There are approximately 800,000 distributive shock cases in the United States per year. Of these cases, an estimated 90% are septic shock patients. Approximately 300,000 do not achieve adequate blood pressure response with current standard therapy. The inability to achieve or maintain adequate blood pressure results in inadequate blood flow to the body’s organs and tissue and is associated with a mortality rate exceeding most acute conditions requiring hospitalization.

Conference Call at 8:30 a.m. Eastern Time on December 22, 2017

The Company will host a conference call and webcast at 8:30 a.m. Eastern Time (5:30 a.m. Pacific Time) on December 22, 2017. The conference call can be accessed by dialing 877‑359‑9508 for domestic callers and 224‑357‑2393 for international callers. Please provide the operator with the passcode 7979625 to join the conference call or click here for the webcast. A slide presentation accompanying today’s press release and the conference call may also be found on La Jolla’s website at www.ljpc.com thirty minutes prior to the call under the investor relations section. An archive of the conference call and webcast will be available on La Jolla’s website for 30 days following the call.

About La Jolla Pharmaceutical Company

La Jolla Pharmaceutical Company is a biopharmaceutical company focused on the discovery, development and commercialization of innovative therapies intended to significantly improve outcomes in patients suffering from life-threatening diseases. Giapreza (angiotensin II), formerly known as LJPC-501, was approved by the U.S. Food and Drug Administration in December 2017 as a vasoconstrictor to increase blood pressure in adults with septic or other distributive shock. La Jolla plans to make Giapreza available for patients in the U.S. starting in March 2018. LJPC‑401 (synthetic human hepcidin) is being developed for the potential treatment of conditions characterized by iron overload, such as hereditary hemochromatosis, beta thalassemia, sickle cell disease and myelodysplastic syndrome. For more information on La Jolla, please visit www.ljpc.com.

Forward Looking Statement Safe Harbor

This press release contains forward-looking statements as that term is defined in the Private Securities Litigation Reform Act of 1995. These statements relate to expectations regarding future events or La Jolla’s future results of operations. These statements are only predictions or statements of current expectations and involve known and unknown risks, uncertainties and other factors that may cause actual results to be materially different from those anticipated by the forward-looking statements. La Jolla cautions readers not to place undue reliance on any such forward-looking statements, which speak only as of the date they were made. Certain of these risks, uncertainties and other factors are described in greater detail in La Jolla’s filings with the U.S. Securities and Exchange Commission (SEC), all of which are available free of charge on the SEC’s website www.sec.gov. These risks include, but are not limited to, risks relating to: the timing for commercial launch of Giapreza (angiotensin II); the degree of physician or pharmacy and therapeutics committee adoption of Giapreza and La Jolla’s success in commercializing Giapreza; the timing and availability of Giapreza in the market; the anticipated treatment of future clinical data by the FDA, the EMA or other regulatory authorities, including whether such data will be sufficient for approval of Giapreza in the EMA and for approval of other product candidates by either the FDA or EMA; risks relating to the scope of the Giapreza product label; potential market sizes, including for septic or other distributive shock; potential indications for which La Jolla’s products and product candidates may be developed; the anticipated timing for regulatory actions; the timing, costs, conduct and outcome of clinical studies; the impact of pharmaceutical industry regulation and healthcare legislation in the United States; and the success of future development activities. La Jolla expressly disclaims any intent to update any forward‑looking statements to reflect the outcome of subsequent events.

Company Contacts

Sandra Vedrick

Director, Investor Relations & Human Resources

La Jolla Pharmaceutical Company

Phone: 858 207 4264 Ext: 1135

Email: svedrick@ljpc.com

and

Dennis M. Mulroy

Chief Financial Officer

La Jolla Pharmaceutical Company

Phone: 858 207 4264 Ext: 1040

Email: dmulroy@ljpc.com

La Jolla Pharmaceutical Company Announces Initiation of Pivotal Clinical Study of LJPC-401 in Patients with Beta Thalassemia

SAN DIEGO, CA – December 4, 2017 – La Jolla Pharmaceutical Company (NASDAQ: LJPC) (the Company or La Jolla) today announced the initiation of a pivotal clinical study of LJPC-401 (synthetic human hepcidin) in patients with transfusion-dependent beta thalassemia who, despite chelation therapy, have cardiac iron levels above normal. A high level of cardiac iron puts patients at risk of cardiac complications such as heart failure and sudden death.

LJ401-BT01 is a pivotal, multinational, multicenter, randomized, controlled study that is designed to enroll approximately 100 patients across 9 countries, including the United States. Patients will be randomized 1:1 to receive either: (i) weekly subcutaneous injections of LJPC-401, while continuing standard-of-care chelation therapy (LJPC-401 treatment arm); or (ii) a continuation of standard-of-care chelation therapy only (observation arm). After 6 months of treatment, patients randomized to the observation arm will crossover to receive LJPC-401 (plus standard-of-care chelation therapy) for 6 months, while patients randomized to the LJPC-401 treatment arm will continue with LJPC-401 (plus standard-of-care chelation therapy) for an additional 6 months (for a total of one year).

The primary efficacy endpoint of this study is the change in iron content in the heart after 6 months, as measured by cardiac magnetic resonance imaging (MRI). La Jolla had previously announced that it had reached agreement with the European Medicines Agency (EMA) on the design of this registration study of LJPC-401.

“It is an important moment for all of those involved in the research of blood diseases. For the first time, it is possible to explore in humans the therapeutic potential of a natural master regulator of body iron,” said Professor Antonio Piga, M.D., Department of Clinical and Biological Sciences School of Medicine, San Luigi Gonzaga University Hospital in Torino, Italy.

“We are pleased to initiate this pivotal study at leading research centers in the U.S. and worldwide,” said George F. Tidmarsh, M.D., Ph.D., President and Chief Executive Officer of La Jolla. “We look forward to continuing the research and development efforts of LJPC-401, with a goal of helping patients suffering from iron overload disorders.”

About LJPC-401

La Jolla is developing LJPC-401 (synthetic human hepcidin) for the potential treatment of iron overload, which occurs as a result of diseases such as hereditary hemochromatosis (HH), beta thalassemia, sickle cell disease (SCD) and myelodysplastic syndrome (MDS). Hepcidin, an endogenous peptide hormone, is the body’s naturally occurring regulator of iron absorption and distribution. In healthy individuals, hepcidin prevents excessive iron accumulation in vital organs, such as the liver and heart, where it can cause significant damage and even result in death. The European Medicines Agency (EMA) Committee for Orphan Medicinal Products (COMP) has designated LJPC-401 as an orphan medicinal product for the treatment of beta thalassemia intermedia and major and SCD.

In September 2016, La Jolla reported positive results from a Phase 1 study of LJPC-401 in patients at risk of iron overload suffering from hereditary hemochromatosis, thalassemia and SCD. Single, escalating doses of LJPC-401 were associated with a dose-dependent, statistically significant reduction in serum iron. LJPC-401 was well-tolerated with no dose-limiting toxicities. Injection-site reactions were the most commonly reported adverse event and were all mild or moderate in severity, self-limiting and fully resolved.

In December 2017, La Jolla announced the initiation of a pivotal, multinational, multicenter, randomized, controlled study of LJPC-401 in patients with transfusion-dependent beta thalassemia who, despite chelation therapy, have cardiac iron levels above normal. La Jolla had previously announced that it had reached agreement with the European Medicines Agency (EMA) on the design of this registration study of LJPC-401.

About Beta Thalassemia

Beta thalassemia is a disease characterized by a genetic mutation that results in the underproduction of hemoglobin, the body’s natural oxygen-carrying molecule contained in red blood cells. There are three types of beta thalassemia: beta thalassemia minor, beta thalassemia intermedia and beta thalassemia major. Patients with the more severe forms (intermedia and major) suffer from significant and sometimes life-threatening anemia, bone deformities and enlargement of the spleen, and usually require frequent and life-long blood transfusions. These blood transfusions cause excessive iron accumulation in the body, which is toxic to vital organs, such as the liver and heart. In addition, the underlying anemia causes excessive iron accumulation independent of blood transfusions.

About La Jolla Pharmaceutical Company

La Jolla Pharmaceutical Company is a biopharmaceutical company focused on the discovery, development and commercialization of innovative therapies intended to significantly improve outcomes in patients suffering from life-threatening diseases. The Company has several product candidates in development. LJPC-501 (synthetic human angiotensin II) is being developed for the potential treatment of hypotension in adult patients with distributive or vasodilatory shock who remain hypotensive despite fluid and vasopressor therapy. LJPC-401 (synthetic human hepcidin) is being developed for the potential treatment of conditions characterized by iron overload, such as hereditary hemochromatosis, beta thalassemia, sickle cell disease and myelodysplastic syndrome. For more information on La Jolla, please visit www.ljpc.com.

Forward Looking Statement Safe Harbor

This press release contains forward-looking statements as that term is defined in the Private Securities Litigation Reform Act of 1995. These statements relate to future events or the Company’s future results of operations. These statements are only predictions or statements of current expectations and involve known and unknown risks, uncertainties and other factors, that may cause actual results to be materially different from those anticipated by the forward-looking statements. The Company cautions readers not to place undue reliance on any such forward- looking statements, which speak only as of the date they were made. Certain of these risks, uncertainties and other factors are described in greater detail in the Company’s filings with the U.S. Securities and Exchange Commission (SEC), all of which are available free of charge on the SEC’s website www.sec.gov. These risks include, but are not limited to, risks relating to: the timing, costs, conduct and outcome of clinical studies; the anticipated treatment of future clinical data by the FDA, the EMA or other regulatory authorities, including whether such data will be sufficient for approval; the timing and prospects for approval of LJPC-501 or LJPC-401 by the FDA, the EMA or other regulatory authorities; risks relating to the scope of product labels (if approved); potential market sizes; the success of future development activities; potential indications for which the Company’s product candidates may be developed; the anticipated timing for regulatory actions; the impact of pharmaceutical industry regulation and healthcare legislation in the United States; and the success of future development activities. The Company expressly disclaims any intent to update any forward-looking statements to reflect the outcome of subsequent events.

Company Contacts

Sandra Vedrick

Associate Director, Investor Relations & Human Resources

La Jolla Pharmaceutical Company Phone: 858 207 4264 Ext: 1135

Email: svedrick@ljpc.com

and

Dennis M. Mulroy

Chief Financial Officer

La Jolla Pharmaceutical Company Phone: 858 207 4264 Ext: 1040

Email: dmulroy@ljpc.com

Media Contact

Matt Middleman, M.D. LifeSci Public Relations Phone: 646-627-8384

Email: matt.middleman@lifescipublicrelations.com

La Jolla Pharmaceutical Company Announces Intent to Submit Marketing Authorization Application for LJPC-501 in the Third Quarter of 2018

— Decision follows successful Scientific Advice meeting with European Medicines Agency —

 

SAN DIEGO, CA – September 25, 2017 – La Jolla Pharmaceutical Company (NASDAQ: LJPC) (the Company or La Jolla) today announced that the European Medicines Agency’s (EMA) Committee for Medicinal Products for Human Use (CHMP) has issued favorable Scientific Advice regarding the EU regulatory pathway for LJPC-501 (angiotensin II) for the treatment of hypotension in adults with distributive or vasodilatory shock who remain hypotensive despite fluid and vasopressor therapy. Based on this Advice, La Jolla intends to submit a Marketing Authorization Application (MAA) for LJPC-501 in the third quarter of 2018.

About LJPC-501

LJPC-501 is La Jolla’s proprietary formulation of synthetic human angiotensin II. Angiotensin II is a major bioactive component of the renin-angiotensin-aldosterone system (RAAS). The

RAAS system is one of three central regulators of blood pressure. LJPC-501 is a vasopressor that leverages the RAAS system. LJPC-501 is being developed for the treatment of patients with distributive or vasodilatory shock who remain hypotensive despite fluid and vasopressor therapy (catecholamines and/or vasopressin).

In August 2017, the Company announced that its New Drug Application (NDA) for LJPC-501 had been accepted for review by the U.S. Food and Drug Administration (FDA). The review classification for the application is Priority, and the user fee goal date under the Prescription Drug User Fee Act (PDUFA) is February 28, 2018. The NDA is based on results of the ATHOS- 3 (Angiotensin II for the Treatment of High Output Shock) multicenter, randomized, double- blind, placebo-controlled, Phase 3 clinical study of LJPC-501 in patients with distributive or vasodilatory shock who remain hypotensive despite fluid and vasopressor therapy. The study was conducted under a Special Protocol Assessment (SPA) agreed to with the FDA in 2015. A total of 344 patients were randomized across nine countries, 321 of whom received study treatment and were included in the primary analysis. In May 2017 the results of the ATHOS-3 study were published by The New England Journal of Medicine in an article entitled “Angiotensin II for the Treatment of Vasodilatory Shock”.

About Patients with Distributive or Vasodilatory Shock Failing Standard Therapy

Distributive or vasodilatory shock (dangerously low blood pressure with adequate cardiac function) can become life-threatening when a patient is unable to achieve or maintain target mean arterial pressure (MAP) despite treatment with the currently available standard of care (fluids and vasopressors). This life-threatening syndrome has been described as clinically refractory hypotension, catecholamine resistant hypotension, high-dose vasopressor-dependent shock, catecholamine or vasopressor refractory shock, or catecholamine-resistant vasodilatory shock. There are approximately 500,000 distributive or vasodilatory shock patients in the United States per year with an estimated 200,000 patients failing standard therapy. Approximately 50% of these patients die within 30 days.

About La Jolla Pharmaceutical Company

La Jolla Pharmaceutical Company is a biopharmaceutical company focused on the discovery, development and commercialization of innovative therapies intended to significantly improve outcomes in patients suffering from life-threatening diseases. The Company has several product candidates in development. LJPC-501 is La Jolla’s proprietary formulation of synthetic human angiotensin II for the treatment of hypotension in adult patients with distributive or vasodilatory shock who remain hypotensive despite fluid and vasopressor therapy. LJPC-401 is La Jolla’s proprietary formulation of synthetic human hepcidin for the potential treatment of conditions characterized by iron overload, such as hereditary hemochromatosis, beta thalassemia, sickle cell disease and myelodysplastic syndrome. LJPC-30S is La Jolla’s next-generation gentamicin derivative program that is focused on the potential treatment of serious bacterial infections as well as rare genetic disorders, such as cystic fibrosis and Duchenne muscular dystrophy. For more information on La Jolla, please visit www.ljpc.com.

Forward Looking Statement Safe Harbor

This press release contains forward-looking statements as that term is defined in the Private Securities Litigation Reform Act of 1995. These statements relate to future events or the Company’s future results of operations. These statements are only predictions or statements of current expectations and involve known and unknown risks, uncertainties and other factors, that may cause actual results to be materially different from those anticipated by the forward-looking statements. The Company cautions readers not to place undue reliance on any such forward- looking statements, which speak only as of the date they were made. Certain of these risks, uncertainties, and other factors are described in greater detail in the Company’s filings with the

U.S. Securities and Exchange Commission (SEC), all of which are available free of charge on the SEC’s web site www.sec.gov. These risks include, but are not limited to, risks relating to: the timing and prospects for approval of LJPC-501 by the FDA, EMA and other regulatory authorities; risks relating to the scope of product labels (if approved); potential market sizes; the anticipated timing for regulatory actions; the impact of pharmaceutical industry regulation and health care legislation in the Europe and the United States; and the success of future development activities. The Company expressly disclaims any intent to update any

forward-looking statements to reflect the outcome of subsequent events.

Company Contacts

Sandra Vedrick

Associate Director, Investor Relations & Human Resources

La Jolla Pharmaceutical Company Phone: 858-256-7910

Email: svedrick@ljpc.com

and

Dennis M. Mulroy

Chief Financial Officer

La Jolla Pharmaceutical Company Phone: 858-433-6839

Email: dmulroy@ljpc.com

Media Contact

Matt Middleman, M.D. LifeSci Public Relations Phone: 646-627-8384

Email: matt.middleman@lifescipublicrelations.com