As in many countries, patent claims directed to methods of medical treatment are not allowable in China. Claims for inventions based on methods of treatment must currently be rewritten in the so-called “Swiss” format. This raises an issue when the invention involves only changes in the dosage regime or timing of administration.
In a recent Supreme Court decision in China, the patentability of a Swiss-type claim was considered where the distinguishing features were a lack of skeletal muscle toxicity, a treatment dose of 3-75mg/kg of daptomycin and the treatment dose being administered at a dose interval of 24 or 48 hours. Cubist Pharmaceuticals Inc appealed against the invalidation of the patent, but the Supreme Court ruled that Swiss-type claims are directed to the method of manufacturing a medicament only and features relating to administration and/or the effect after administration should be disregarded. The decision discussed the distinction between unit dose and an administration or treatment dose and confirmed that a treatment dose does not affect the manufacturing process of a medicament and therefore does not limit a Swiss-type claim.
It is possible that specifying that the dose is a unit dose or claiming the packaging as part of the manufacturing process where the packaging states the dosage regime could overcome this issue but this is yet to be tested.