Antares Pharma, Inc. has submitted new drug application (NDA) to the US Food and Drug Administration (FDA) for Otrexup, a combination product for the delivery of methotrexate (MTX) using Medi-Jet technology. Otrexup was developed for easy subcutaneous administration of MTX to enhance the treatment of rheumatoid arthritis (RA), poly-articular-course juvenile RA and moderate to severe psoriasis.

“The NDA submission of Otrexup represents yet another significant accomplishment in the Company’s history,” said Paul K Wotton PhD., president and chief executive officer. “It is the first product designed for convenient subcutaneous delivery of methotrexate in patients with rheumatoid arthritis or psoriasis. We believe Otrexup will benefit most patients that have not reached a satisfactory response to oral methotrexate alone or in combination with a biologic or another disease-modifying anti-rheumatic drug.”

Otrexup was developed to optimize the clinical benefit of MTX, leading to cost effective treatment outcomes. Historically, parenteral MTX use has been limited in clinical practice for several reasons including the inconvenience of weekly intramuscular injections by a healthcare professional, and/or the challenges associated with teaching patients with impaired hand function, safe and sterile self-injection techniques. Studies conducted to date indicate Otrexup is safe, easy and comfortable for RA patients to self-administer precise subcutaneous doses of MTX with improved systemic availability compared to oral doses.

The NDA submission, subject to acceptance and approval by the FDA, was supported by data generated from a clinical development programme completed in accordance with the FDA’s guidance and recommendations. Antares executed and completed all of the clinical studies agreed with the agency and described in the clinical development programme.

“The dedicated efforts of the entire Antares team have allowed us to submit a New Drug Application to the FDA ahead of schedule,” said Kaushik J Dave R.Ph., PhD., executive vice president Product Development said, “The results from the clinical development programme have shown that Otrexup can provide greater systemic exposure to methotrexate compared to oral doses. We believe Otrexup is easy to use and comfortable for RA patients with moderate to severe hand function impairment thereby enhancing self-administration and patient compliance.”

Medi-Jet is a proprietary parenteral drug delivery system protected by several issued and pending patents. Medi-Jet is designed to enable patients to quickly and easily self-administer a drug subcutaneously or intramuscularly, reliably and comfortably while also enhancing safety with an integrated, shielded needle that protects against accidental needle stick and drug exposure. Medi-Jet is a trademark of Antares Pharma.

Methotrexate is a commonly prescribed disease-modifying anti-rheumatic drug (DMARD), used in an estimated 70 per cent of rheumatoid arthritis patients either on its own or in combination with biological therapies. Methotrexate is started at a low dose, generally 7.5mg given orally, once-a-week, and titrated up for greater therapeutic effect, or until the patient incurs side effects. The maximum oral dose given is generally 20mg to 25mg per week.

Published studies have reported that 30 per cent to 60 per cent of patients experience gastrointestinal side effects with oral methotrexate, preventing further dose escalation or requiring discontinuation in some patients. Oral absorption of methotrexate varies considerably between patients and between doses in the same patient and has been shown to decline with increasing doses, which may also contribute to insufficient therapeutic response even after dose escalation. Switching patients from oral to parenteral methotrexate improves absorption and has been associated with improved therapeutic response. Additionally, some studies have shown a lower incidence of gastrointestinal side effects in patients that were switched from oral to parenteral methotrexate.

Rheumatoid Arthritis is a form of inflammatory arthritis and an autoimmune disease. In rheumatoid arthritis, the immune system – which is designed to protect our health by attacking foreign cells such as viruses and bacteria – instead attacks the body’s own tissues, specifically the synovium, a thin membrane that lines the joints. As a result of the attack, fluid builds up in the joints, causing pain in the joints and inflammation that’s systemic – meaning it can occur throughout the body. Rheumatoid arthritis is a chronic, incurable disease. Most people with RA experience intermittent bouts of intense disease activity, called flares. In some people the disease is continuously active and gets worse over time. Evidence shows that early diagnosis and treatment to put the disease into remission is the best means of avoiding joint destruction, organ damage and disability.

Psoriasis is a chronic, autoimmune disease that appears on the skin. It occurs when the immune system sends out faulty signals that speed up the growth cycle of skin cells. Psoriasis is not contagious. There are five types of psoriasis. The most common form, plaque psoriasis, appears as raised, red patches covered with a silvery white build-up of dead skin cells. Psoriasis can occur on any part of the body and is associated with other serious health conditions, such as diabetes, heart disease and depression. Psoriasis is the most common autoimmune disease in the US. According to the National Psoriasis Foundation, as many as 7.5 million Americans have psoriasis.

Antares Pharma focuses on self-administered parenteral pharmaceutical products and topical gel-based medicines.