The shares of Natco Pharmaceuticals have risen after the Intellectual Property Appellate Board (IPAB) dismissed an appeal from AstraZeneca on lung cancer drug Gefitinib.

AstraZeneca had tried to get a patent for Gefitinib from the Indian Patent Office in 2007 but it did not get the patent on the grounds of known prior use. The Patent Office had accepted pre- grant opposition by Natco Pharma. Industry estimates show that the sales of Gefitinib are expected to be about Rs 60 crore to Rs 70 crore this year.

IPAB has dismissed an appeal from pharma major Bayer Corporation for a stay on an order of the Controller of Patents that granted compulsory licence to Natco Pharma for the drug. IPAB upheld its decision on November 26 not to grant AstraZeneca a patent claim in 2007 due to lack of invention.

"We are disappointed by the Intellectual Property Appellate Board's decision. We are confident in the validity of the claims in this patent application and are now evaluating our next steps," AstraZeneca said in a statement.

The shares of Natco Pharma opened at Rs 422 and hit a record high of Rs 468 on the Bombay Stock Exchange (BSE).