A cancer drug in development at Pfizer that has shown promising efficacy in a Phase III trial involving patients with stomach cancer who have failed to respond to Novartis’ Gleevec/Glivec (imatinib), has been granted orphan drug status by the European Commission.

Last week, Pfizer reported that the results of its Phase III trial in gastrointestinal stromal tumour were so positive that the trial’s ethical committee has recommended that it be halted, so patients who were taking placebo can now be switched to receive SU11248 [[09/02/05c]].

SU11248, a novel oral multi-targeted cancer therapy that combines anti-angiogenic and anti-tumour activity to simultaneously stop the blood supply to and directly attack tumour cells, was originally developed by biotechnology company Sugen, which was acquired by Pharmacia, and then became part of Pfizer [[16/04/03d]].

In the latest trial, SU11248 was administered to patients with GIST, the most frequent form of gastrointestinal cancer, according to Novartis, and highly resistant to traditional treatment with chemotherapy and radiation. The treatment of GISTs was traditionally surgery but has been revolutionised by the introduction of Gleevec. However, up to 50% of patients do not respond to Novartis’ drug [[24/09/04a]].

“We are encouraged by this interim data analysis and believe this is a positive step towards establishing SU11248 as an option for patients with Gleevec-resistant GIST,” said Dr Joseph Feczko, Pfizer’s president of worldwide development.

SU11248 is also being studied in Phase III trials as a potential treatment for renal cell carcinoma. At last year’s American Society of Clinical Oncology meeting, Pfizer reported unprecedented efficacy in patients with RCC who had already filed treatment with interferon-alpha, the primary therapy for the disease. SU11248 achieved a 33% partial response rate, plus stabilisation of disease in a further 37% of patients [[07/06/04f]].

- In addition to granting orphan status to SU11248, the European Commission orphan drug committee also backed Chiron’s treatment Pulminiq (cyclosporine for inhalation) for preventing and treating graft rejection after lung transplants, and Johnson & Johnson’s Zarnestra (tipifarnib) for acute myeloid leukaemia.