US-based biopharmaceutical company SpringWorks Therapeutics has received the US Food and Drug Administration (FDA) approval for Ogsiveo (nirogacestat) to treat a rare subtype of soft tissue tumours.

Ogsiveo is an oral, selective, small-molecule gamma-secretase inhibitor indicated for the treatment of adult patients with progressing desmoid tumours who require systemic treatment.

Desmoid tumours are rare, locally aggressive, and invasive tumours of the soft tissues that can be serious and may be life-threatening in certain cases when vital structures are impacted.

Traditionally, surgical removal of tumours has been the treatment of choice, which is associated with health challenges after removal.

According to the US-based biopharmaceutical company, Ogsiveo is the first FDA-approved treatment for adult patients with desmoid tumours.

The FDA approval of Ogsiveo follows previously granted breakthrough therapy, fast track, and orphan drug designations, for the treatment of desmoid tumours.

SpringWorks CEO Saqib Islam said: “We are pleased with the broad label, which includes all progressing adult patients and specifically references improvement in pain and believe Ogsiveo has the potential to become the new standard of care for people living with these devastating tumours.

“This is a watershed moment for the desmoid tumour community, and we would like to extend our gratitude to the patients, families, investigators, and advocacy groups involved in the journey to making Ogsiveo available in the US.”

The FDA approval of Ogsiveo is supported by the results from the Phase 3 DeFi trial in which 142 adult patients with progressing desmoid tumours who are not eligible for surgery.

In the Phase 3 study, the drug met the primary endpoint of improving progression-free survival (PFS), showing a 71% reduction in the risk of disease progression, compared to placebo.

Ogsiveo also showed a confirmed objective response rate (ORR) of 41% and a complete response rate of 7%, compared to 8% and 0% for placebo, respectively.

The PFS and ORR improvements were regardless of sex, tumour location, tumour focality, treatment status, previous treatments, mutational status, and history of familial polyposis.

The drug also showed improvements in patient-reported outcomes (PROs), including pain, desmoid tumour-specific symptoms, physical functioning, and overall quality of life.

In the Phase 3 DeFi trial, the Ogsiveo showed a manageable safety and tolerability profile.

The most common adverse events include diarrhoea, ovarian toxicity, rash, nausea, fatigue, stomatitis, headache, abdominal pain, cough, alopecia, upper respiratory tract infection, and dyspnoea.

Furthermore, SpringWorks is evaluating Ogsiveo as a potential treatment for ovarian granulosa cell tumours and multiple myeloma as part of several BCMA combination therapy regimens.