In a new twist in the patent fight between Roche and Cipla, India’s Drug Controller General wants the generic drugmaker to explain accusations that it was promoting its version of Roche’s Tarceva cancer med for an unapproved use. The charge was leveled by a Roche distributor, according to LiveMint. If the regulator concludes Cipla acted improperly, the generic drugmaker could be charged with violating the Drugs and Cosmetics Act of 1940, according to one industry expert.

In a March 27 letter, Taksal Pharma, a distributor for Roche Scientific, alleged Cipla was distributing promotional literature on Erlocip to doctors for treating four kinds of cancers, even though it didn’t have regulatory approval for using the drug to treat all four cancers. Roche itself has only secured approval for Tarceva to be used for non small-cell lung cancer and pancreatic cancer.

“Cipla is promoting the drug for neck and head cancer as well as colorectal cancer, besides the two indications that Roche has approval for. They are selling it for uses that even the innovator hasn’t discovered,” claimed one industry person close to the development, LiveMint reports. This person, who didn’t want to be named, says Cipla only had approval for using its drug to treat lung cancer. The drug is being sold in India as Erlocip by Cipla.

Roche Scientific’s managing director, Girish Telang, confirmed that Taksal had written to the regulator. “They have brought it to our notice. We have written to Cipla, asking them to respond within a specific time frame. We will give them a chance to make their standpoint clear, produce scientific evidence supporting their claims to doctors and then take appropriate action. It is a serious issue,” controller Surinder Singh tells LiveMint.

Singh said his office could issue a warning to Cipal asking it to desist and, in an extreme case, even cancel its manufacturing license. A response from Cipla was expected early next week, he adds. Amar Lulla, Cipla’s ceo, says he couldn’t immediately comment on the issue as he was out of India and unaware of the development.

Even though Roche had a patent on the drug, Cipla had gone ahead with marketing of its version in India. The issue snowballed into a high-decibel patent infringement lawsuit before the Delhi high court, with Roche asking for an injunction to restrain Cipla from selling cheaper copies of its drug.

In turn, Cipla filed a counter-complaint seeking to revoke the Tarceva patent, alleging that the drug was merely a tweaked version of a pre-1995 drug and, hence, ineligible for patent protection under Indian law. The generic drugmaker says its version costs a third of the Roche drug, while Roche blamed its higher prices on the steep import duties.

The court quashed Roche’s injunction plea a month ago, saying barring cheaper copies will cause irreparable harm to the patients. Roche then filed an appeal before a larger bench in the same court last week and hearings are continuing on the Tarceva patent revocation case.

According to information available under the National Cancer Control Programme, cancer has become one of the 10 leading causes of death in India, with nearly 1.5-2 million cases at any given point of time. Another statistic from Indian Council of Medical Research shows that in India at least 90,000 men and 79,000 women are diagnosed each year with lung and bronchial cancer alone.