Bristol’s faith in Tyk2 pays off

Bristol Myers Squibb’s decision to sell Celgene’s psoriasis drug Otezla to Amgen to keep its hands on the Tyk2 inhibitor deucravacitinib looked bold at time, but it appears to have paid off. In the first phase III trial to read out, Poetyk-PSO-1, a 6mg/day dose of deucravacitinib not only beat placebo but also bested Otezla, a fellow oral agent. Bristol is saving the full data for a scientific meeting, but investors will hope for a repeat of deucravacitinib’s phase II study, in which PASI 75 response rates of up to 75% were seen – well ahead of the 33% rate observed with Otezla. Safety readings will also have to be competitive; all Bristol has said is that side effects were consistent with earlier trials. Despite its lower efficacy, Otezla is considered a safer option than biologicals, and has sold well. But Bristol has long claimed that deucravacitinib has efficacy in line with biologicals, with oral convenience. If the full results of Poetyk-PSO-1 bear this out and deucravacitinib (BMS-986165) makes it to market Otezla could be hit hard. Another phase III study of deucravacitinib versus Otezla, Poetyk-PSO-2, is set to read out in the first quarter of 2021.