Votrient (pazopanib) has been approved by the FDA for the treatment of soft tissue sarcoma in patients who have already received chemotherapy. Soft tissue sarcoma is a type of cancer that starts in the fibrous tissue blood vessels, fat, muscle, or other supporting tissue in the body. The cancer develops in the mesenchymal cells. Votrient stops blood vessels that feed the tumor from growing and surviving – it stops angiogenesis.

Soft tissue sarcoma is a rare cancer which has several subtypes. In the USA, approximately 10,000 people are diagnosed with soft tissue sarcoma annually. 10,980 cases were diagnosed in 2011.

GlaxoSmithKline (GSK) presented the FDA with data from a clinical trial that covered over 20 sarcoma subtypes when it submitted Votrient for approval. It has not been approved for those with gastrointestinal stromal tumors and adipocytic soft tissue sarcoma.

Director of the Office of Hematology and Oncology Products, Center for Drug Evaluation and Research, FDA, Richard Pazdur, M.D., said:

“Soft tissue sarcomas are a diverse group of tumors and the approval of Votrient for this general class of tumors is the first in decades. Drug development for sarcomas has been especially challenging because of the limited number of patients and multiple subtypes of sarcomas.”

Votrient’s safety and efficacy evaluation came from one clinical study involving 369 individuals; they all had received chemotherapy beforehand and had advanced soft tissue sarcoma. They were selected, at random, to receive either a placebo or Votrient. Progression-free survival was measured (how long patients survived without cancer progressing).

Progression-free survival was:

  • 4.6 months for those on Votrient
  • 1.6 months for those on the placebo

Undesirable side effects reported by those on Votrient included nausea, weight loss, hypertension, decreased appetite, muscle pain, change in hair color, headache, change in sense of taste, breathlessness, skin discoloration, vomiting, diarrhea, and fatigue.

Paolo Paoletti, M.D., President, GSK Oncology, said:

“It is such a great moment to bring forth this treatment option for patients, as it represents one of the few new medical options to be provided to patients with advanced soft tissue sarcoma over the last thirty years.

GSK Oncology feels fortunate to have collaborated with the European Organization for Research and Treatment of Cancer (EORTC) in completing a rigorous Phase III trial in such a rare cancer.”

The drug carries a boxed warning, alerting doctors and patients about the risk of potentially fatal hepatotoxicity (liver damage). It is important that liver function be monitored while the patient is on Votrient. If there are any signs of liver function decline, Votrient therapy should be discontinued.

Votrient, which was initially approved for advanced kidney cancer treatment in 2009, was granted an orphan drug status designation for soft tissue sarcoma.

Written by Christian Nordqvist