In shooting down the global pharmaceutical giant’s bid for the interlocutory relief, Justice Stephen Burley on Wednesday said Alphapharm had raised a “sufficiently strong” early challenge to the novelty of Sanofi’s injector pen patent and that it was “doubtful” that Sanofi had established a strong enough infringement case to warrant the injunction.

Sanofi Deutschland and Sanofi Australia filed the case against Alphapharm in August, alleging infringement of the patent behind its reusable Allstar Pro injector pen and seeking to block Alphapharm from listing its Semglee injector pen on the PBS.

Justice Burley sided with Alphapharm in finding there was strong enough early evidence that claim 1 of Sanofi’s patent was anticipated by two pieces of prior art to undermine the strength of its infringement claim.

The judge also raised concerns about Sanofi’s construction of claim 1 of the patent, saying “it appears to seek to introduce impermissible glosses to the language of the claim”, and expressed “disquiet” about the approach of the expert the drug giant relied on to bolster its construction.

“I am not prepared to say that Sanofi’s defence of the invalidity challenge is unarguable. It may well be that on a final hearing it will meet the difficulties to which I have referred in relation to the construction of claim 1 of the Patent and the prior art documents. But difficulties they are. They affect the assessment at the present time of the probability that if on a final hearing the evidence remains the same Sanofi will be entitled to final injunctive relief for the infringement of claim 1,” Justice Burley said.

The judge did not contest that the introduction of the Semglee pen would cause harm to Sanofi, including a price drop of at least 25 per cent for its three PBS-listed injector pens. And while the judge said the balance of convenience was “quite evenly balanced”, he ultimately found the harm suffered by Alphapharm if the injunction were granted would be “significant and less readily compensated by an award of damages” than it would be for Sanofi if the injunction were denied.

“[T]he calculation of loss likely to be suffered by Alphapharm having regard to a hypothetical launch is likely to be more difficult as a vehicle for recompense than the calculation of loss for Sanofi, even taking into account the consequential effects of price drops that arise because Semglee is listed on the PBS Schedule and the uncertainties associated with future market conditions,” the judge said.

Sanofi claims the Semglee pen is the same as its own AllStar Pro and infringes on its patent covering the delivery device. Both pens allow users to adjust the dose of medication, such as Insulin Glargine, injecting the medication on their own to treat conditions such as diabetes.

In addition to the patent infringement claims, Sanofi alleges Alphapharm has breached the Australian Consumer Law through misleading and deceptive conduct.

Jones Day represents Sanofi-Aventis. MinterEllison represents Alphapharm.

The case is Sanofi-Aventis Deutschland GmbH & Anor v Alphapharm Pty Ltd.