HRX-215 is an orally bioavailable MKK4 inhibitor for liver regeneration. In just over a decade since they discovered the dual specific kinase MKK4 as a master regulator of hepatocyte regeneration, HRX-215 completed a FIH clinical trial. This article is a fascinating case study on harnessing the liver's natural regenerative capacity, identifying key regulators of liver regeneration, and leveraging a kinase inhibitor with reported off-target activity for MKK4 as a suitable starting point, among other insights.

EOS-984 is an oral, potential first-in-class, highly selective ENT1 inhibitor from iTeos currently in clinical trials for advanced solid tumors. The drug, which was identified through SBDD and optimization of the vasodilator dilazep, targets the immunosuppressive effects of adenosine, which helps tumors evade immune detection. This is an excellent case study on the importance of understanding a molecule's bioactive conformation to reduce the entropy of binding and enhance potency.

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?

BAY 2413555 is a M2R PAM that has the potential to counter parasympathetic withdrawal and restore autonomic balance in heart failure patients. The preclinical and clinical data of BAY 2413555 showed it has positive effects on heart rate and heart rate variability and a relatively long human t1/2 of 37 h. The Ph. I trial, however, was terminated in March 2024 due to findings from a chronic toxicology study. This article covers the discovery of BAY 2413555, presented by Alexandros Vakalopoulos of Bayer at the EFMC-ISMC 2024 conference in Rome and published in the Journal of Medicinal Chemistry.

Chiesi Farmaceutici’s CHF-6523 is an inhaled, lung-restricted, selective PI3Kδ inhibitor designed to provide relief to patients with COPD. Its development involved optimization of permeability and solubility as well as identification of a solid form amenable for dry powder inhalation. Disclosed at the EFMC-ISMC 2024 joint conference in Rome, Italy, this article covers the structure, development, and early clinical data of CHF-6523, which ultimately indicates that PI3Kδ inhibition may not provide clinical effect in reduction of lung inflammation.