GlaxoSmithKline has received an Indian Patent No. 213203 (the ‘203 patent) for a novel hydrate form of Rosiglitazone Maleate against the mail-box Application No. IN/PCT/2000/00076/MUM filed December 14, 1998 claiming earliest priority from British patent application dated December 16, 1997. The ‘203 patent titled ‘Hydrate of 5-[4-[2-(N-methyl-N-(2-pyridil) amino) ethoxy] benzyl] thiazolidine-2, 4-dione maleic acid salt’ is lately published in the Patent Office Journal Issue No. 04/2008. Abstract of IN/PCT/2000/00076/MUM reads as –
A hydrate of 5-[4-[2-(N-methyl-N-(2-pryidyl) amino) ethoxy] benzyl] thiazolidine-2, 4-dione, maleic acid salt, characterised in that it: (i) contains water in the range of from 0.2 to 1.1% w/w, and (ii) provides an infrared spectrum containing peaks at 764 and 579 cm-1; and/or (iii) provides an X-ray powder diffraction (XRPD) pattern substantially as set out in Figure II; a process for the preparation of such a compound, a pharmaceutical composition containing such a compound and the use of such a compound or composition in medicine.
Rosiglitazone Maleate, globally marketed as Avandia is patented anti-diabetic drug in US and EU valid till October 2015 and September 2014 respectively. Although not sure exactly in what form claims are issued by the Mumbai Patent Office, but certainly would be interested knowing that. For close reference, refer equivalent US Patent Nos. 6,664,278 and 7,045,633.