Repare Therapeutics Inc (NASDAQ:RPTX) reported initial proof of concept monotherapy data from its Phase 1 MYTHIC trial evaluating lunresertib (RP-6306) in molecularly selected advanced solid tumors.
Preliminary antitumor activity was observed, including moderate tumor shrinkages and a confirmed partial response.
Several patients demonstrated long stable disease and remained on treatment for greater than 11 months and ongoing.
Early clinical combination insights demonstrated greater antitumor activity in patients treated with lunresertib plus camonsertib than lunresertib alone.
The tolerability profile of lunresertib monotherapy appears favorable and differentiated from other clinical cell cycle inhibitors, characterized by myelotoxicity and diarrhea.
The only dose-limiting toxicity was reversible rash, alleviated with dose modifications and simple, supportive measures.
Two recommended doses/schedules were identified – 240mg daily continuously and 80-100mg BID intermittent weekly – to offer maximum flexibility in combination studies.
The pharmacodynamic analysis confirmed lunresertib treatment results in PKMYT1 target inhibition at active doses and increased DNA damage.
Repare is also currently evaluating lunresertib combined with gemcitabine in the Phase 1 MAGNETIC study and with FOLFIRI in the Phase 1 MINOTAUR study.
Price Action: RPTX shares closed at $11.65 on Wednesday.
