October 1, 2018Regulatory
First drug granted approval under FDA's Limited Population Pathway for Antibacterial and Antifungal Drugs, instituted to spur development of antibiotics for unmet medical needs
Mycobacterium avium complex (MAC) is a type of nontuberculous mycobacteria (NTM) commonly found in water and soil. Symptoms of disease in patients with MAC include persistent cough, fatigue, weight loss, night sweats, and occasionally shortness of breath and coughing up of blood. The FDA has approved a new drug, Arikayce (amikacin liposome inhalation suspension), for the treatment of MAC in a limited population of patients with the disease who do not respond to conventional treatment (refractory disease).
Arikayce is the first drug to be approved under the Limited Population Pathway for Antibacterial and Antifungal Drugs, or LPAD pathway, established by Congress under the 21st Century Cures Act to advance development and approval of antibacterial and antifungal drugs to treat serious or life-threatening infections in a limited population of patients with unmet need. Approval under the LPAD pathway may be supported by a streamlined clinical development program. These programs may involve smaller, shorter or fewer clinical trials. As required for drugs approved under the LPAD pathway, labeling for Arikayce includes certain statements to convey that the drug has been shown to be safe and effective only for use in a limited population.
Arikayce also was approved under the Accelerated Approval pathway. Under this approach, the FDA may approve drugs for serious or life-threatening diseases or conditions where the drug is shown to have an effect on a surrogate endpoint that is reasonably likely to predict a clinical benefit to patients. The approval of Arikayce was based on achieving three consecutive negative monthly sputum cultures by month six of treatment. The sponsor of Arikayce will be required by the FDA to conduct an additional, post-market study to describe the clinical benefits of Arikayce.
The safety and efficacy of Arikayce, an inhaled treatment taken through a nebulizer, was demonstrated in a randomized, controlled clinical trial where patients were assigned to one of two treatment groups. One group of patients received Arikayce plus a background multi-drug antibacterial regimen, while the other treatment group received a background multi-drug antibacterial regimen alone. By the sixth month of treatment, 29% of patients treated with Arikayce had no growth of mycobacteria in their sputum cultures for three consecutive months compared to 9 percent of patients who were not treated with Arikayce.
The Arikayce prescribing information includes a Boxed Warning regarding the increased risk of respiratory conditions including hypersensitivity pneumonitis (inflamed lungs), bronchospasm (tightening of the airway), exacerbation of underlying lung disease and hemoptysis (spitting up blood) that have led to hospitalizations in some cases. Other common side effects in patients taking Arikayce were dysphonia (difficulty speaking), cough, ototoxicity (damaged hearing), upper airway irritation, musculoskeletal pain, fatigue, diarrhea and nausea.
The FDA granted this application Fast Track, Breakthrough Therapy, Priority Review, and Qualified Infectious Disease Product (QIDP) designations. QIDP designation is given to antibacterial products that treat serious or life-threatening infections under the Generating Antibiotic Incentives Now (GAIN) title of the FDA Safety and Innovation Act. Arikayce also received Orphan Drug designation, which provides additional incentives to assist and encourage the development of drugs for rare diseases.
The FDA granted approval of Arikayce to Insmed, Inc. of Bridgewater, NJ.