Sun Pharmaceutical and Novartis have been in dispute over a second medical use patent, EP 1296689 (‘689 patent), which relates to the treatment of osteoporosis using a specific acid, zoledronic acid. It was granted on September 21, 2005. Novartis developed a medicine with zoledronic acid as an active ingredient that is used in the oncological field. Novartis commercialises the product with zoledronic acid as the active compound under the trademark ‘Zometa’.