Despite the remarkable emergence of HAART in the 1990s, the fight against HIV infection is by no means finished. At the ACS Fall 2024 meeting in Denver, CO, Gilead Sciences presented the structure and discovery story of elunonavir (GS-1156), a novel HIV protease inhibitor with remarkable metabolic stability and a human half-life exceeding two weeks. Based on BMS’ atazanavir, the compound incorporates structural elements inspired by Gilead’s HCV NS5A inhibitor program which led to ledipasvir, as “stabilizer” motifs to avoid the extensive CYP metabolism seen in current inhibitors.

Genentech’s divarasib is a KRASG12C inhibitor in Ph. III for non-small cell lung cancer, making it the most advanced KRASG12C inhibitor after the accelerated approvals of Amgen’s sotorasib and Mirati’s adagrasib. Efficacy with the molecule positions it well at a pivotal moment following sotorasib's recent FDA setback and BMS’s acquisition of adagrasib. Why divarasib is a big deal and what's notable about it in this full article.

This month’s cover molecule, Pfizer’s PF-07321332 (nirmatrelvir, API of Paxlovid) is an oral, reversible covalent SARS-CoV-2 main protease inhibitor, which has been submitted to the FDA by Pfizer for emergency approval for Covid treatment. Interim data showed Paxlovid reducing Covid hospitalization and death by 89%. It was nominated for this month’s [...]

Pfizer’s ritlecitinib, a first-in-class, selective, oral covalent inhibitor of JAK3 and the TEC family of kinases, was FDA-approved in June 2023 for the treatment of severe alopecia areata. Ritlecitinib derives its JAK-family kinase selectivity from the covalent modification of a unique cysteine on JAK3. This annotation reviews the discovery of ritlecitinib, highlighting the interpretation of selectivity assays, the PK optimization, the evolution of the JAK3 therapeutic hypothesis, and how this 2023 Molecule of the Year nominee has become a classic case study for covalent drug discovery.

Last year, Biogen announced that it would acquire Texas biotech Reata Pharmaceuticals for $7.3B. Reata’s lead molecule, omaveloxolone (SKYCLARYS®), an oral, reversible covalent inhibitor of the E3 ligase KEAP1, became the first drug approved for Friedrich’s Ataxia. Omaveloxolone was previously highlighted as a Molecule of the Month in July 2023. Now, this 2023 Molecule of the Year nominee reflects a historic milestone for neurological drug discovery. This comprehensive explainer dives into Nrf2 target rationale, how it works, how the drug was discovered, its synthesis, and why it’s a big deal.