“King Keytruda’s reign continues,” analysts at BMO Capital Markets declared after Chinese data for Summit Therapeutics’ ivonescimab were revealed at the American Society for Clinical Oncology in Chicago.
The applause has faded for Akeso’s ivonescimab presentation at the American Society for Clinical Oncology (ASCO) annual meeting, leaving behind key questions for American partner Summit Therapeutics.
While the Phase 3 lung cancer trial in Chinese patients showed what analysts and clinicians had been looking for—a 34% reduction in the risk of death—Summit will now have to replicate the results in a population more representative of the U.S. market.
“Does the totality of the Invonescimab data from HARMONi-6 point to broad efficacy across patient types? Simply put, we do not know,” BMO Capital Markets wrote to investors on Sunday after having time to digest the presentation.
The data from Akeso’s HARMONi-6 trial showed that treatment with ivonescimab plus chemotherapy led to an overall survival (OS) rate of 27.9 months, compared to 23.7 months in the arm that received BeOne’s Tevimbra plus chemotherapy.
The results appeared to release some pressure on Summit, which is testing a broader population in a Phase 3 trial called HARMONi-3 with a readout due in the second half. The biotech’s shares fell just under 4% in pre-market trading on Monday morning.
Turns out, however, that Summit’s pressure cooker is just getting powered up as analysts digest the data. The four-month overall survival benefit with a hazard ratio of 0.66 met analysts’ sky-high expectations. But the population was in what BMO called a “non-representative population of young, Chinese men with lung cancer who had smoked.
“Generally speaking, these data are good (worthy of a plenary, you be the judge), but provide little insight into the potential benefit of ivonescimab in a global population,” the analysts wrote.
The Akeso data also showed little difference in survival for patients over 65 as compared to chemo alone.
Merck’s immuno-oncology stalwart Keytruda has shown worse efficacy in older patients, BMO said. The drug’s key trial in this indication also had a somewhat better gender balance with 79% male patients.
Also revealed at ASCO was the lack of long-term follow up in the HARMONi-6 study, which tracked patients for just 21 months.
“While helpful in providing initial glimpses at ivonescimab’s efficacy, this limited follow-up leaves room for treatment survival advantage to regress with time as more patient data is available at a longer time point,” BMO said.
Keytruda is the drug that ivonescimab is trying to unseat. In September 2024, ivonescimab was 49% more effective than Keytruda at reducing risk of disease progression or death in the Phase 3 HARMONi-2 trial, though analysts advised caution that the results were in a China-only population.
With the new data presented at ASCO, BMO declared that: “King Keytruda’s reign continues.”
Still, oncology experts are optimistic about Summit’s chances. One key opinion leader heralded the survival benefit as “one of the most important in NSCLC,” according to Truist Securities. This expert believes Summit will be able to reproduce the result in a global study, with ivonescimab becoming a key part of a new standard of care treatment combination for the first-line setting.
Summit will also likely have first-to-market advantage over rivals Bristol Myers Squibb and BioNTech, which are together developing pumitamig. The expert believes the PD-(L)1/VEGF market could ultimately be served by just two entrants.
BMS and BioNTech also presented data over the weekend, with pumitamig showing comparative response data to ivonescimab, according to Truist. The Phase 2 ROSETTA Lung-02 trial showed a 70% overall objective response rate and 100% disease control rate. Ivonescimab scored a 76% ORR in earlier trials.
