New Drug Application (NDA)

The NDA is the complete case for a new drug: all investigations of safety and effectiveness, chemistry manufacturing and controls, non-clinical data, proposed labelling and any risk management plan. The legal test is substantial evidence of effectiveness from adequate and well-controlled investigations, long read as two independent positive trials, with FDA guidance now allowing one such trial plus confirmatory evidence. Peptides of forty or fewer amino acids are approved on this pathway; larger molecules take a biologics licence.

The clock comes from user-fee goals rather than statute. FDA takes sixty days to decide whether the application is complete enough to file, then works to a goal date roughly ten months from filing for a standard review or six for a priority one. The outcome is approval or a complete response letter, which since 2008 replaced the older approvable letters and sets out what must be fixed; deficiencies are often manufacturing or facility issues rather than efficacy. FDA has recently begun publishing complete response letters that were formerly confidential.

For reading a company's claims, the vocabulary needs care. Submitted, filed, accepted for review, given a goal date and approved are five different states, and only the last authorises marketing. The approved labelling that emerges is narrower than the application, since indications the sponsor failed to support do not appear in it.

One mistake is reading a complete response letter as a scientific rejection, when the same application is often approved after a resubmission with no new clinical data. The mistake that matters more here is the reverse: a grey-market peptide described as pending FDA approval usually has no application of any kind, since a pending NDA is a public, dated, sponsor-attributed fact.