Molecule Spotlight: Risdiplam, the First Approved Small Molecule Splicing Modulator for Spinal Muscular Atrophy

In 2021 there were: 50 novel drugs approved by the FDA 27 that CDER considers first-in-class (FIC) 16 first-in-class small molecules (according to CDER) These drugs are the first in their therapeutic class to have a particular mechanism of action [...]

together with Dr. Jennifer Huen, Saumil Patel, and Dr. Naveed Yasin In 2021, the FDA approved 9 non-radiological novel small molecule drugs for oncology. Excluding melphalan flufenamide, which has already been withdrawn, the remaining FDA-approved novel small molecule oncology drugs of 2021 are: umbralisib (PI3Kδ and CK1ε inhibitor) sotorasib [...]

Leniolisib is a selective PI3Kδ inhibitor that received approval in March 2023 from the FDA as a first-in-class treatment for activated PI3K-δ syndrome (APDS), a genetic immunodeficiency disorder caused by PI3Kδ activation. The leniolisib discovery program is notable for several reasons: it is a first approval for a PI3K inhibitor outside of oncology; the first approved drug for APDS; has a novel chemotype that appears to avoid safety issues that led to black box warnings seen with other PI3K molecules; and it overcame a polymorph issue with an early lead that led to inconsistent exposures.

The team reviews hundreds of compounds from thousands of papers, press releases, and other sources each month to select candidates for Molecules of the Month. Here we have compiled a table of >70 additional molecules that were of interest in November 2023 along with some highlights from some of our favorites below.

This deep dive into 2021’s novel large molecule drug approvals is the 2 nd in a series of focus articles on 2021’s novel large molecule drugs. See part one here . For each of the 16 large molecule drug approvals of 2021 (excluding vaccines), we’ll [...]