FDA okays first therapy for desmoid tumours from SpringWorks

Pfizer spin-out SpringWorks Therapeutics has its first approved product after getting a green light from the FDA for Ogsiveo, the first-ever therapy for a rare type of non-cancerous tumour that can significantly impair patients’ quality of life.

Ogsiveo (nirogacestat) has been cleared as an oral, first-line therapy for adult patients with progressing desmoid tumours who require systemic treatment. Desmoid tumours are not malignant but can nevertheless be locally aggressive, invading neighbouring tissues and causing symptoms including pain, disfigurement and mobility problems.

There are around 7,000 people in the US currently receiving treatment for the tumours, with up to 1,500 new cases diagnosed every year, according to company estimates.

The new product has been approved after a priority review by the FDA and also picked up fast-track and breakthrough designations, pointing to the pressing need for a licensed therapy for desmoid tumours, which are currently treated mainly with thermal ablation, radiotherapy and surgical procedures that lack efficacy and can be costly and dangerous.

In the DeFi trial involving 142 adults with progressing desmoid tumours, Ogsiveo achieved a significant 71% improvement in progression-free survival (PFS) compared to placebo, with an overall response rate of 41% and 8%, respectively, including 7% complete responses with the active drug.

Nirogacestat is an oral gamma-secretase inhibitor working via the Notch signalling pathway and was originally developed by Pfizer, which spun the programme out into SpringWorks in 2017 along with three other drug candidates.

“Desmoid tumours can have a significant impact on people’s lives and are difficult to manage due to their invasive nature and high rates of recurrence,” said DeFi investigator Mrinal Gounder of Memorial Sloan Kettering Cancer Centre.

“Ogsiveo is a highly innovative therapy with efficacy data demonstrating both meaningful antitumour activity and a significant improvement in desmoid tumour symptoms [and] is an important therapeutic advance for patients,” he added.

SpringWorks also has aspirations to expand the use of Ogsiveo into other forms of cancer, and to that end, is working with GSK to combine the drug with BCMA-targeted antibody-drug conjugate Blenrep (belantamab mafodotin) for blood cancer multiple myeloma, based on the hypothesis that inhibiting gamma-secretase can potentiate the effects of BCMA-targeting drugs.

GSK signed a $575 million partnership with SpringWorks to explore that rationale last year, shortly before it had to pull Blenrep from the market as a fourth-line or later multiple myeloma therapy after failing a confirmatory trial. Yesterday, however, GSK reported new data suggesting Blenrep could be heading back to the US market as a second-line therapy.