Introduction

Second medical use patents introduce a new therapeutic use for existing active ingredients. These patents are an important and effective way to extend the patent life of medicines. However, a recent case shows that second medical use patents can be difficult to enforce in light of substitution rules.

In a preliminary decision on June 25 2015, the Maritime and Commercial High Court balanced the substitution rules against the protection of second medical use patents. The court decided in favour of the second medical use patent.

Facts

Pfizer originally held a product patent for pregabalin (marketed as Lyrica) which was used for epilepsy and generalised anxiety disorder. This patent expired. However, a second medical use patent covering the use of pregabalin for pain relief is still active.

In January 2015 Krka obtained marketing authorisation for Pregabalin Krka (a generic version of Lyrica) for the treatment of epilepsy and generalised anxiety disorder. The marketing authorisation did not include pain relief. The product was introduced on the Danish market on March 2 2015.

The Danish substitution rules prescribe that Danish pharmacies must supply patients with the cheapest alternative if multiple medicines have the same effects. The Health and Medicines Authority is of the opinion that the substitution must take place even if some indications are covered by a second medical use patent. As a result, the authority has advised pharmacies that these drugs should be used as substitutes, even if the prescription specifies pain relief.

Pfizer disagreed with this position and filed a request for a preliminary injunction against Krka and 220 pharmacies to prevent the dispensing of Pregabalin Krka for pain relief. The authority intervened on behalf of the defendants.

Decision

The court found that the pharmacies' supply of Pregabalin Krka affixed with a label stating that it was designed for the treatment of pain constituted an infringement of Pfizer's patent. The court further noted that neither the Medicinal Products Act nor any other regulatory laws provide any clear exemption to such patent rights. Consequently, the court granted an injunction against the 220 pharmacies dispensing Pregabalin Krka for pain relief. However, the court did not grant an injunction against Krka.

Pfizer's primary claim that Krka should be prohibited from selling Pregabalin Krka without ensuring that the drug was not dispensed for pain relief was found to be too vague to be enforced by a court of law.

Pfizer's secondary claim related to Krka selling Pregabalin Krka to Danish wholesalers and pharmacies without "sending an explicit instruction" that Pregabalin Krka cannot be dispensed for pain relief. Nine days after the request for the preliminary injunction was filed, Krka sold the products to the pharmacies with a specific instruction that the drugs were not to be dispensed for pain relief. Based on this, the court also dismissed Pfizer's secondary claim against Krka.

Comment

The case seems to indicate that if a generic manufacturer instructs wholesalers that the generic medicine cannot be dispensed for the treatment of the second medical use, the generic producer does not infringe the second medical use patent, even if the medicine is subsequently dispensed for treatment of the second medical use.

The case also indicates that if a medicine is prescribed for a patented second medical use, the obligation on pharmacies to dispense the cheapest product (ie, a generic version approved for the first medical use) does not permit the pharmacies to dispense the generic version. The substitution rules do not overrule the patent.

The case is a preliminary decision only and may be appealed to the High Court.

For further information on this topic please contact Jeppe Brinck-Jensen or Anders Poulsen at Accura Advokatpartnerselskab by telephone (?+45 3945 2800) or email (jeppe.brinck-jensen@accura.dk or anders.poulsen@accura.dk). The Accura Advokatpartnerselskab website can be accessed at www.accura.eu.

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