FDA Approves Firdapse® (Amifampridine) for the Treatment of Lambert-Eaton Myasthenic Syndrome (LEMS)

– First evidence-based drug approved to treat LEMS

– Catalyst Pathways ™ designed to facilitate access to Firdapse® and provide dedicated patient support

– Launch at the beginning of the first quarter of 2019

– Catalyst will hold a conference call on December 13, 2018 at 8:30 am ET to discuss launch details

CORAL GABLES, Florida, November 29, 2018 (GLOBE NEWSWIRE) – Catalyst Pharmaceuticals, Inc. (Catalyst) (Nasdaq: CPRX), a biopharmaceutical company specializing in the development and commercialization of innovative therapeutics for patients with rare chronic neuromuscular and debilitating diseases . neurological diseases, announced today that the US Food and Drug Administration (FDA) has approved 10 mg tablets of Firdapse® (amifampridine) for the treatment of Lambert-Eaton's Syndrome (LEMS) in the United States. # 39; adult. Firdapse is expected to be available on the market early in the first quarter of 2019. Comprehensive information on prescription click here.

"The approval of Firdapse by the FDA is a potentially critical step in the lives of American patients with LEMS because it now allows adult patients to benefit from a new, first-rate therapy," said Patrick J. McEnany, chairman of the board of directors. and Chief Executive Officer of Catalyst Pharmaceuticals. "The approval of Firdapse is an ultimate achievement for our company and an important step in our transition to a leading society in the field of rare neurological diseases. We continue to prepare for what we hope will be a successful launch based on productive discussions with payers, our patient identification efforts and our development of a field-based commercial infrastructure. Our Catalyst Pathways ™ The Patient Services Program is designed to help patients and physicians with education, clinical diagnostic tools and navigational aid in the reimbursement landscape. "

"I am pleased that the FDA has recognized the complete clinical data supporting the benefits of Firdapse for patients with LEMS," said Perry B. Shieh, MD, Ph.D., Department of Neurology at UCLA Medical Center. "It is important that patients with this debilitating disease now have access to an FDA-approved treatment that has shown clinically significant benefits."

LEMS is a rare autoimmune disease that affects approximately 1 in 100,000 people in the United States. The most common symptoms of LEMS are proximal muscle weakness and fatigue. The symptoms can be life-threatening when the weakness is in the respiratory muscles. About 50% of LEMS patients have an underlying malignancy, typically small cell lung cancer.

"At the National Organization for Rare Disorders (NORD), it's a great day for patients when we learn that the FDA has approved an essential treatment for a rare disease. We would like to congratulate the entire Catalyst team for its commitment to providing LEMS patients and their physicians with access to an FDA-approved drug, "said Peter Saltonstall, President and CEO of NORD. "With 95% of rare diseases still having no FDA approved treatment, ongoing research and new products remain of vital importance to the rare disease community."

The presentation of the Firdapse NDA came as a result of the positive results of two phase 3 studies in which Firdapse-treated patients exhibited a rapid, significant and lasting improvement in muscle function, as well as a reduction in weakness and fatigability compared to patients receiving placebo. These benefits have been observed by patients and physicians. Please see below for important safety information. Firdapse had previously received the Orphan Drug Title, the Advanced Therapy Title, as well as the FDA's Priority Review. Firdapse is the first and only drug approved in Europe for the treatment of LEMS.

"This FDA approval marks the arrival of a leading treatment for a rare and devastating condition with limited treatment options," said Gary Ingenito, MD, Ph.D., chief physician and chief of business. regulatory requirements at Catalyst. "We express our deepest gratitude to the patients who participated in Firdapse clinical trials, as well as to their families and the caregivers who supported them. We are also grateful for the tireless efforts of investigators and study staff, without whom this important milestone would not have been possible. We are also looking forward to continuing to work with the FDA to evaluate other potential indications of Firdapse. "

Catalyst Pathways ™

Catalyst Pathways ™ is an optional, free, personalized program that offers patients and their families individual support throughout treatment, with a dedicated team of specialists to help them manage their unique challenges. The Catalyst Pathways Patient Support Team includes a care coordinator with extensive health care experience; an insurance browser, to help them understand their insurance coverage and the drug allocation process; a patient support liaison to help them understand their illness and their prescription, and a specialized pharmacy experienced in helping patients with rare diseases to direct delivery of prescriptions. The Catalyst Pathways support team also helps registered patients understand and access financial assistance options for eligible patients, including a copay program designed to minimize the burden patient for his patients. For more information on Catalyst Pathways click here.

Conference call

Catalyst will host a teleconference and webcast to discuss its Firdapse marketing plan, including the cost of treatment, on December 13, 2018 at 8:30 am ET. Investors wishing to participate in the teleconference may do so by calling (877) 407-8912 for Canadian and Canadian callers or (201) 689-8059 for international callers. Those wishing to listen to the live teleconference via the Internet can do so by visiting the Investors page of the Company's website at www.catalystpharma.com and clicking on the Webcast link on the web page. Home Investors. A replay of the webcast will be available on the Catalyst website after the call by visiting the Investors page of the company's website at the address https://www.catalystpharma.com.

About Lambert-Eaton Myasthenic Syndrome (LEMS)

LEMS, is a rare autoimmune disease, most often characterized by fatigable muscle weakness of the limb. The disease is caused by autoantibodies to voltage-gated calcium channels located in the nerve-muscle junction, resulting in poor nerve-muscle communication, leading to progressive muscle weakness, when they are not treated. In about 50% of cases, LEMS is associated with an underlying malignant tumor, most often small cell lung cancer, and in some individuals, LEMS is the first symptom of this tumor. LEMS usually affects the extremities, especially the legs. At the onset of the disease, the muscles closest to the trunk are affected, which makes it difficult to climb the stairs or to get up from a sitting position. Physical exercise and high temperatures tend to aggravate the symptoms. The weakness of the muscles of the mouth, throat and eyes is sometimes observed. People with LEMS may also have autonomic disruption, with symptoms of dry mouth, dry skin, constipation, blurred vision, impaired sweating, and / or inappropriate changes in blood pressure.

About Firdapse® (amifampridine)

Firdapse® (amifampridine) 10 mg tablet is an oral, nonspecific, voltage-dependent potassium channel blocker (K ​​+) that causes depolarization of the presynaptic membrane and slows or inhibits repolarization. This action causes the opening of slow calcium channels (Ca2 +) depending on the voltage, allowing a subsequent influx of Ca2 +. In turn, it induces exocytosis of synaptic vesicles containing acetylcholine (ACh) to release more ACh in the synaptic cleft, which improves neuromuscular transmission and improves muscle function. Firdapse is approved in the United States and the European Union for use by patients with LEMS.

Important safety information

CONTRAINDICATIONS

FIRDAPSE is contraindicated in patients with:

• A history of seizures
• Hypersensitivity to amifampridine phosphate or other aminopyridine

WARNINGS AND PRECAUTIONS

The seizures: FIRDAPSE can cause convulsions. Consider stopping treatment or reducing the dose of FIRDAPSE in patients who have a seizure during treatment. FIRDAPSE is contraindicated in patients with a history of seizures.

L & # 39; hypersensitivity: If a hypersensitivity reaction such as anaphylaxis occurs, treatment with FIRDAPSE should be discontinued and appropriate therapy instituted.

SIDE EFFECTS

The most common adverse reactions (> 10%) are: paresthesia, upper respiratory tract infection, abdominal pain, nausea, diarrhea, headache, elevated liver enzyme levels, back pain, hypertension, and muscle spasms.

To report SUSPECTED REACTIONS, contact Catalyst Pharmaceuticals at 1-844-347-3277 (1-844-FIRDAPSE) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

About Catalyst Pharmaceuticals

Catalyst Pharmaceuticals is a biopharmaceutical company specializing in the development and commercialization of innovative therapies for people with debilitating and debilitating chronic neuromuscular and neurological diseases, including LEMS, congenital myasthenic syndromes (CMS), myasthenia gravis with anti-MuSK antibodies ( MuSK-MG) and the disease of the spine. (SMA) type 3. Amifampridine phosphate has received the orphan drug designation of the United States FDA for CMS and myasthenia gravis. Firdapse (amifampridine), a 10 mg tablet, is the first and only drug approved in Europe for the symptomatic treatment of LEMS in adults.

Catalyst is also developing a generic version of vigabatrin.

Forward-looking statements

This press release contains forward-looking statements. Forward-looking statements involve known and unknown risks and uncertainties that may cause the actual results of Catalyst to differ materially from those projected in future periods. A number of factors, including (i) whether Catalyst will succeed in commercializing Firdapse (ii) if, even if Catalyst succeeds in marketing Firdapse, Catalyst will become profitable, (iii) if Firdapse will ever be approved for CMS processing. , MuSK-MG, SMA type 3 or other illness, and (iv) the other factors described in Catalyst's Annual Report on Form 10-K for fiscal 2017 and other filings with the US Securities and Exchange Commission. Exchange Commission (SEC), could harm the catalyst. Copies of Catalyst filings with the SEC are available from the SEC, the Catalyst website or Catalyst upon request. Catalyst assumes no obligation to update the information contained in this document, which is only valid from that date.