FDA Allows In Vitro Studies to Demonstrate Naloxone Bioequivalence

For the development of generic versions of naloxone, an emergency nasal spray treatment for opioid overdoses, the FDA said it will allow sponsors to demonstrate bioequivalence using solely in vitro performance tests — as long as the generic is qualitatively the same as the reference product.

For both 2 mg and 4 mg doses, the FDA recommended applicants conduct studies in each strength using samples from three or more batches of the test product—evaluating single spray actuation content, droplet size distribution, drug in small particles or droplets, spray pattern and plume geometry.

The agency also described an in vivo option in its product-specific draft guidance, if the test product is not qualitatively the same as the reference. In that case, sponsors should conduct a fasting study, examining a single dose at 4 mg in healthy volunteers. Sponsors should evaluate naloxone blood levels at four, 10 and 30 minutes following administration.

The FDA referred sponsors to previous guidance on the development of generic fluticasone nasal sprays for general recommendations on study design and data submission. The agency also recommended sponsors request a pre-ANDA meeting with the Office of Generic Drugs, and submit results of comparative analyses, including any identified differences to the reference product.