Genentech said Friday that it could have to wait up to three more months before it hears whether the US Food and Drug Administration will approve its breast cancer drug Herceptin for patients in the early stages of the disease.
The FDA has asked for more time to review the dossier after Genentech submitted additional information which the agency has classified as a ‘major amendment’ to the file. It was originally due to rule on the application this Thursday.
The new information is a re-analysis of data from previously-submitted studies, said Genentech in a statement.
At the moment, Herceptin (trastuzumab) is approved in the USA to treat tumours of the breast that express the HER-2 protein and have spread outside the breast, but Genentech wants to extend that indication to include the treatment of women with early-stage disease as an adjunct to surgery.
Roche, which holds a majority stake in Genentech, said Herceptin won approval in early HER-2-positive breast cancer in Europe in May. The Swiss drugmaker reported sales of 1.8 billion Swiss francs for Herceptin in the first six months of this year, while Genentech reported sales of $610 million for the drug in the same period.
The new submission is based on an interim analysis of more than 3,000 patients with early-stage breast cancer enrolled in two Phase III trials.
The patients enrolled in the trial received either Herceptin with paclitaxel or paclitaxel alone, after the initial treatment of surgery and four cycles of chemotherapy with anthracycline and cyclophosphamide.
The results showed that addition of Herceptin to standard adjuvant therapy reduced the risk of breast cancer recurrence by 52%, which was a statistically significant improvement.
A follow-on of the study showed that 13% of women treated with Herceptin plus chemotherapy saw their disease recur, compared to 25% of women treated with chemotherapy alone. In addition there was a 49% improvement in overall survival of patients treated with Herceptin plus chemotherapy.