Genmab pushes rina-S into its third phase 3

After months of anticipation Genmab is ready to launch the Rainfol-04 trial, its third phase 3 study of rinatabart sesutecan, the anti-folate receptor alpha (FRα) ADC originated by ProfoundBio. The start, however, will come slightly later than originally projected by the company.

According to a new clinicatrials.gov listing the study is now expected to begin in January 2026, instead of the second half of 2025. It will evaluate rina-S as second-line maintenance therapy in platinum-sensitive ovarian cancer patients with HRD mutations, including BRCA, and the asset will be tested with or without Avastin, versus Avastin or observation, which represents the standard of care in this indication. PFS is the primary endpoint.

The design is quite similar to that of AbbVie’s Gloriosa study, which is testing Elahere in the same setting, and is expected to read out in early 2027. The main difference appears to be that AbbVie’s trial only includes FRα-high patients, while Genmab’s study does not appear to select patients based on FRα status.

Lilly, meanwhile, is also evaluating its FRα-targeting ADC LY4170156 in platinum-sensitive ovarian cancer, as part of the Framework-01 trial, which also includes platinum-resistant patients. In both disease subtypes patients are required to have been previously treated with a PARP inhibitor, something neither Genmab’s nor AbbVie’s trials specify.

Notably, in Lilly’s study the platinum-sensitive patients will receive LY4170156 plus Avastin, or Avastin plus chemo – with no mention of purely observation, providing a contrast with Genmab’s trial.

So far, Lilly appears to have the most powerful anti-FRα ADC, based on its latest results presented at ESMO. There, the company reported responses in patients with low FRα expression, a subgroup where Elahere hasn't shown strong activity. Genmab, while not yet sharing detailed data, has also reported responses in patients with folate receptor alpha expression below 75%, though the rates appear to be lower than those achieved by Lilly’s candidate.

 

Phase 3 studies of anti-FRα ADCs in platinum-sensitive ovarian cancer 

Source: OncologyPipeline.