pas-004

PAS-004 is a next-generation, macrocyclic small molecule that acts as an allosteric inhibitor of MEK1 and MEK2, dual-specificity protein kinases in the MAPK signaling pathway. By selectively binding to and inhibiting MEK1/2, PAS-004 blocks downstream activation of ERK and other effector proteins, leading to inhibition of cell proliferation and tumor growth. The drug is being developed by Pasithea Therapeutics for the treatment of neurofibromatosis type 1 (NF1), Noonan syndrome, advanced solid tumors with MAPK pathway mutations (including RAS, NF1 or RAF mutations), and potentially other cancers. Unlike earlier generation MEK inhibitors that require twice-daily dosing due to short half-lives (<8 hours), PAS-004 has a significantly longer half-life (~70 hours) allowing for once-daily or less frequent dosing with more stable plasma concentrations. This pharmacokinetic profile may reduce peak-related toxicities commonly seen with other MEK inhibitors. Preclinical studies have shown potent activity against NRAS mutant cancer cell lines and favorable safety data; early clinical trials indicate good tolerability without typical adverse effects such as rash or GI toxicity[1][2][3][4][5][6][7][8].