Cancer drug Tarceva (erlotinib) can cause holes in intestine, warns US FDA

Anti-cancer drug Tarceva can cause dangerous side-effects including skin reactions, eye problems and holes in the digestive tract, the US Food and Drug Administration warned consumers and healthcare professionals.

Tarceva, which contains erlotinib, is currently approved for two types of lung and pancreatic cancers. Tarceva treats locally advanced or metastatic non-small cell lung cancer that has not responded to at least one prior chemotherapy treatment. It also is approved for use, along with gemcitabine, to treat locally advanced pancreatic cancer.

However, Tarceva treatment risks of severe and in some cases fatal injuries in patients.

Patients taking Tarceva have developed fatal gastrointestinal perforations, blistering and exfoliative skin conditions that are suggestive of Stevens-Johnson Syndrome (also called toxic epidermal necrolysis). Some patients also have reported suffering severe eye injuries, including corneal perforations and ulceration, according to the FDA.

In some cases, patients under Tarceva medication, have died, USFDA said.

The FDA has just issued a warning letter to healthcare professionals to detail the problems associated with Tarceva.

Tarceva comes in pill form to be taken orally once a day on an empty stomach that is designed to block cell tumor cell growth by targeting the protein in the body called the Human Epidermal Growth Factor Receptor 1. The drug works by inhibiting the tyrosine kinase activity of the HER1 signaling pathway inside the cancerous cell.

FDA approved Tarceva in November 2004 to treat some types of lung cancer. Tarceva got FDA nod to be used for treatment of certain forms of pancreatic cancer in November 2005.

Tarceva is made by a partnership of Genentech Inc (now a subsidiary of Swiss drug maker Roche) and OSI Pharmaceutical Inc.

OSI spokesperson said the side-effects reported were not significant as the number of patients who developed serious skin conditions was “in the low single-digit range” out of more than 350,000 patients who have been treated with Tarceva worldwide.

Tarceva in India

Tarceva, which registered global sales of $1 billion in 2008, was approved in India in April 2006 as a therapy for patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) after failure of at least one prior chemotherapy regimen.

Soon after the launch India’s Cipla Ltd came up with a generic version of erlotinib.

Justifying the launch, Cipla was quoted as saying that it intended to launch their own version of erlotinib at a  lesser price – Rs1,600 ($41) a tablet. Roche’s Tarceva costs around Rs 3,30000 for a 3-month treatment, in India.

Following this, Roche sued Cipla for patent infringement in the Delhi High Court and applied for a temporary injunction. During hearings, Cipla counterclaimed that the patent was invalid and should be revoked.

In its verdict last month the High Court allowed Cipla to manufacture and sell Tarceva by vacating its interim order by which Cipla was restrained from exporting the drug to other countries in which La Roche has patent rights.

The Delhi High Court dismissed the plea of the Swiss company saying that the Indian company should be restrained from manufacturing and selling the generic drug till the issue of patent rights was decided through litigation.

The High Court also imposed a cost of Rs five lakh (US $ 10,000) on Roche.

Again in April, the Indian patent office rejected Roche’s patent application for the polymorph B form of erlotinib hydrochloride on grounds of prior publication. Cipla, in a pre-grant opposition also argued that erlotinib is publicly known and used in India and its polymorphic salt lack in inventiveness.