A letter received from the Kolkata Patent Office confirms that GlaxoSmithKline (GSK) has withdrawn its application no. 872/CAL/1998 for Abacavir Sulfate (marketed as Ziagen). I-MAK helped the Indian Network of Positive People (INP+) file an opposition against the application, which claims the hemisulfate salt of Abacavir.
As we argued in the opposition prepared for INP+, an earlier published patent in 1991 (EP 0434450) already disclosed sulfuric acids as pharmaceutically acceptable acid addition salts for the compound Abacavir, thus anticipating or making the selection of the hemisulfate salt obvious. The opposition also argued that GSK’s claims for a new salt for the ease of large scale manufacture should not amount to efficacy for the purposes of meeting s3(d). However, as a result of GSK’s withdrawal, the opposition proceedings have now ended without the patent office having to rule on these matters.
Interestingly, in October Livemint reported that GSK had withdrawn its application for the ARV combination drug Trizivir (Lamivudine, Zidovudine and Abacavir Sulfate) ‘in the public’s interest’. This statement comes despite the fact that Cipla had opposed the application and that opposition proceedings were ongoing before GSK decided to withdraw it application.
We wonder whether GSK is truly acting in the public interest or is avoiding the build up of case law by the patent office that could serve to hinder other similar applications/granted patents in India and other countries.