The SUCCEED trial using oral ridaforolimus met its primary endpoint of progression-free survival in patients with metastatic soft-tissue or bone sarcomas who had responded well to chemotherapy, Merck announced at the American Society of Clinical Oncology Annual Meeting in Chicago today. Outside the USA and Canada, Merck is known as MSD or ARIAD Pharmaceuticals.

Ridaforolimus is an investigational mTOR (mammalian target of rapamycin) inhibitor. By blocking mTOR, the cancer cells become starved and cannot grow, divide, metabolise or develop new blood vessels properly.

Patients on ridaforolimus had longer PFS (progression-free survival) compared to those on a placebo. Merck says that based on the drug meeting its primary endpoint, MSD will submit a marketing application in the European Union towards the end of this year.

Eric Rubin, M.D., vice president of clinical oncology research at Merck, said:

“These data bring us one step closer to making ridaforolimus available to patients with metastatic sarcoma who need it and reinforces our ongoing commitment to developing innovative therapies to treat cancer.”

SUCCEED stands for the Sarcoma Multi-Center Clinical Evaluation of the Efficacy of Ridaforolimus trial. It was a randomized, double-blind, placebo-controlled study of 40 mg oral ridaforolimus administered once a day, either five or seven days each week in patients with metastatic soft-tissue or bone sarcomas who had received chemotherapy and responded well.

Ridaforolimus achieved a 28% reduction in the risk of progression or death compared to placebo. Those on ridaforolimus had PFS of 17.78 weeks, versus 14.6 weeks in the placebo group.

In a communiqué, Merck wrote:

“Based on the full analysis of PFS determined by investigator assessment, there was a statistically significant (p

70% of those in the ridaforolimus group were alive and free from disease progression compared to 54% in the placebo group after three months, after six months the figures were 34% and 23% respectively.

Patients on ridaforolimus had an average target tumor lesion size reduction of 1.3%, compared to an increase of 10.3% in the placebo group.

Serious side effects:

  • Thrombocytopenia. 10% in the ridaforolimus group, 1% in the placebo group.
  • Stomatitis. 9% in the ridaforolimus group, 1% in the placebo group.
  • Anemia. 7% in the ridaforolimus group, 3% in the placebo group.
  • Hyperglycemia. 7% in the ridaforolimus group, 1% in the placebo group.

Source: Merck

Written by Christian Nordqvist