REC-4881 - (TUPELO)

Nov. 2, 2026: Recursion (NASDAQ: RXRX) reported updated positive Phase 2 data from the ongoing TUPELO trial of REC-4881, an oral MEK1/2 inhibitor for familial adenomatous polyposis (FAP), presented in a Presidential Plenary at the CGA-IGC Annual Meeting.

In adults aged 18+ treated for 12 weeks, 87% (13/15) had reduced total polyp burden, with a 47% median reduction; about one-third achieved reductions of 65% or more. After 12 weeks off treatment, 85% (11/13) remained below baseline. In upper GI disease, 92% (12/13) had reductions, with a 55% median reduction; nearly half achieved reductions of at least 65%, two patients had reductions of at least 98%, and 6/12 improved by at least one Spigelman stage. In lower GI disease, 82% (9/11) had reductions, with a 50% median reduction, and one-third achieved reductions of at least 65%.

For larger polyps (>5 mm), 6/8 patients had fewer such polyps after 12 weeks; 4/8 had reductions of at least 80%, and in two patients counts fell from more than 90 to one. Safety in 26 evaluable patients showed no new signals: Grade 1/2 TRAEs in 21 (80.8%), Grade 3 in four (15.4%), no Grade 4/5 TRAEs, and no new discontinuations since the prior cutoff. The company said it expects to initiate a registrational trial in 2H 2027, pending FDA discussions.