Dosage regimes - "obvious to try" rides again

In a decision which is likely to make it more difficult to patent dosage regimes in future, the Court of Appeal has overturned the High Court’s finding that a patent for a dosage regime for CIALIS was valid. 

CIALIS is used, among other things, for the treatment of male erectile dysfunction.  A key point in the Court’s decision was that although at the time of the invention the discovery that the new dosage regime was effective had been surprising (which might normally suggest that it was not obvious), in this case the invention lay “at the end of the familiar path through the routine pre-clinical and clinical trials process”, and dose ranging studies to find out the dose response relationship were a part of that process. The skilled team would have embarked on this path as a matter of course with a fair expectation that they would find a suitable dosage and there was a high likelihood that this routine process would have led them to the patented dosage regime.  As a result, the invention was to be regarded as obvious – i.e. lacking inventive step – and the patent was invalid.

In “obvious to try” cases there is always a risk that the process of arriving at the invention only seems obvious with hindsight. Recent cases have made it more difficult to invalidate patents on the basis of “obvious to try” by providing that the patent will generally only be invalid for obviousness if the researcher “trying” would have done so with a “reasonable expectation of success”. This case serves as a valuable reminder that merely carrying out industry-standard testing is unlikely to result in a valid patent. The question in any particular case is, of course, whether this is, in fact, all that was done or whether there was an inventive process involved.

The case: Actavis Group PTC EHF v ICOS Corp, Court of Appeal, 1.11.17

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Charlotte Tillett, Astrid Arnold

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