Biologics License Application (BLA)
A formal submission to the US FDA for approval of a biological product, including certain proteins and larger peptides produced by biological processes. Somatropin and romiplostim are regulated as biologics under the BLA pathway, which has different requirements than the NDA used for conventional drugs.
Technical Context
BLAs are regulated under Section 351 of the Public Health Service Act (vs NDAs under Section 505 of the FD&C Act). Key BLA differences: manufacturing requirements emphasise process controls and characterisation (because biological products are defined partly by their manufacturing process — 'the process is the product'), reference product exclusivity is 12 years (vs 5 years data exclusivity for NDA), and the biosimilar pathway (351(k)) requires demonstrating 'high similarity' through stepwise analytical, nonclinical, and clinical comparison. Products regulated as biologics include: recombinant proteins (somatropin, romiplostim), monoclonal antibodies, vaccines, blood products, and gene therapies. The BPCIA (2010) transferred many peptide products from NDA to BLA regulation; the FDA maintains a Purple Book listing approved biological products.