Merck and Lilly expand alliance with Keytruda + Lartruvo trial

Lilly is to test its new sarcoma treatment Lartruvo in combination with Keytruda, representing yet another combination for Merck Inc's immunotherapy blockbuster.

The two companies have been collaborating by conducting trials which combine Lilly’s existing cancer portfolio with Keytruda for around two years, and will now launch trials of the PD-1 immunotherapy with Lartruvo in sarcoma.

Lartruvo was approved by the FDA in October, and is the first new treatment for sarcoma in 40 years, and produced some very impressive improvements over existing drugs.

Median survival from its pivotal trial was 26.5 months compared to 14.7 months for patients who received doxorubicin alone. Median progression-free survival on Lartruvo was 8.2 months compared to 4.4 months for doxorubicin patients, and tumour shrinkage was also doubled.

The companies believe these results could be improved and sustained by the combination with Keytruda.

Lartruvo (olaratumab) is a platelet-derived growth factor receptor alpha (PDGFR-α) blocking antibody that specifically binds PDGFR-α and prevents receptor activation. The companies believe this mode of action could be complimentary to Keytruda’s checkpoint inhibitor mechanism.

However Lartruvo does carry with it some serious side-effects, including nausea, low blood pressure and fever. Investigators will need to balance the combined side-effects of both drugs against the potential benefits of the two drugs administered together.

The US National Cancer Institute is already sponsoring trials of BMS’ rival PD-1 treatment Opdivo in combination with Yervoy in sarcoma, though BMS itself is not currently funding any similar trials itself.