Summit Therapeutics (SMMT) Stock Forecast & Price Target

Summit Therapeutics is viewed favorably because the fundamental data for ivonescimab continue to strengthen, with HARMONi-2 improving its overall survival hazard ratio from 0.777 at 157 deaths to 0.73 at 234 deaths and extending median OS to 30.75 months versus 22.57 months. That resilience suggests meaningful clinical differentiation, especially as the benchmark remains sac-TMT plus pembrolizumab, which posted a stronger 0.35 PFS HR and 70.2% ORR versus 0.51 and 50.0% for ivo, while the pembrolizumab control arm data make the comparison unusually informative. Although sac-TMT’s early 0.55 OS HR at 87 deaths still needs maturation, the improving survival trend and the upcoming HARMONi-3 final PFS/interim OS in 2H26, where a PFS HR of 0.72 or better is expected, support an optimistic long-term outlook.

Summit Therapeutics is viewed negatively because the ivonescimab story still rests on early China efficacy that has not yet translated into mature overall survival, with H-2 showing a 0.51 PFS HR but an immature OS HR of 0.777/0.78 and no promised YE25/early-2026 update. H-6 also raises durability concerns as its PFS HR weakened from 0.60 at 10.28 months to 0.72 at 17.02 months, while H-3 remains blinded and the added interim analysis did not accelerate timing, suggesting less confidence in global translation. On top of that, Merck’s KEYTRUDA and ADC options reduce strategic differentiation, and the high safety burden from combination regimens makes the bar for commercial success even higher.