Nuvalent’s lead compound, NVL-520, is an oral, brain-penetrant, TRK-sparing, and potential best-in-class ROS1 kinase inhibitor that recently entered Ph. II of the ARROS-1 trial (NCT05118789) in patients with advanced ROS1-positive NSCLC. This article highlights what makes the Nuvalent’s NVL-520 program scientifically notable, including what gives it a potential best-in-class profile as a ROS1 inhibitor, the emerging toxicology of hard-to-avoid off-targets, an interesting synthetic route to the small macrocycle, and more.

Tyra Biosciences’ lead asset, TYRA-300, is a potent, selective, and orally bioavailable FGFR3 inhibitor designed to mitigate the toxicities commonly seen with pan-FGFR inhibitors. A key objective of the program was to meet the safety standards required for advancing into pediatric populations for the treatment of ACH (achondroplasia) and other skeletal dysplasias. TYRA-300 is currently being evaluated in Ph. I clinical trials for advanced urothelial cancers and other solid tumors and, importantly, has received IND clearance to initiate a Ph. II clinical trial in pediatric ACH patients.

AbbVie’s ABBV-467 is a highly potent, selective MCL-1 (myeloid cell leukemia-1) inhibitor which entered the clinic in 2022 in a Ph. I trial in patients with advanced hematologic cancers. MCL-1 has had a rough time in the clinic with multiple trials being halted or terminated due to cardiac toxicity, which is suspected to be an on-target effect. AbbVie’s approach with ABBV-467 was to target a highly potent/short half-life compound which could induce rapid apoptosis and tumor regressions in a short exposure period before the onset of any adverse events. Is this the end for MCL-1?

Jecure’s JT001 is a selective inhibitor of NLRP3 inflammasome and among the earlier compounds in this now highly competitive space. In 2018, Genentech bought Jecure Therapeutics for an undisclosed amount, gaining access to Jecure’s NLRP3 inhibitor JT001. While there are many other NLRP3 inhibitors now in the space, JT001 is an interesting example of an initial attempt to overcome liver toxicity with well-known NLRP3 inhibitor MCC950. However, the molecule ran into its own kidney toxicity issues, making this an intriguing toxicology case study.

Revumenib (Revuforj®) is approved by the FDA as an oral, first-in-class menin-MLL interaction inhibitor for acute leukemia (AL). Since inhibition of the menin-MLL fusion protein interaction is selective for AL with a KMT2A translocation, it does not compromise normal hematopoietic function. This article covers the background, optimization and clinical development that has led to the approval of this groundbreaking new drug in a hard-to-treat indication.