ECJ Advocate General says excipient label is binding for SPC purposes: Halozyme v. Czech IPO

Context:

• Supplementary protection certificates (SPCs) are an EU instrument that extends the exclusivity period of pharma patents by up to five years, compensating innovators for the time eaten up by the regulatory approval process before a drug can be sold. Under the SPC Regulation, the active ingredient or a combination of the active ingredient of a medicinal product is considered to be a product and eligible for SPC protection.
• Halozyme, a U.S. biotech corporation, owns EP2163643 (“Soluble hyaluronidase glycoprotein (sHASEGP), process for preparing the same, uses and pharmaceutical compositions comprising thereof”). It was licensed to Roche for use in Herceptin SC, a subcutaneous therapy for breast cancer that includes rHuPH20. Roche identified trastuzumab as the active component and rHuPH20 as an excipient (a non-active element) in the marketing authorization (MA) for Herceptin SC approved by the European Commission (EC) in August 2013.
• The Industrial Property Office (IPO) of the Czech Republic denied Halozyme’s SPC application because rHuPH20 was classified as an excipient in the marketing authorization. Halozyme appealed, and the highest court for administrative disputes in the Czech Republic, the Nejvyši spravni soud, referred six questions to the European Court of Justice (ECJ).

What’s new: Advocate General (AG) Nicholas Emiliou delivered his opinion in Halozyme v. Czech IPO on April 23, 2026. The AG took a strong position in favor of the Czech IPO, as did the EC as well as the Czech, French, Dutch, and Irish governments: a substance expressly described as an excipient in the MA cannot be considered an active ingredient under the provisions of the SPC Regulation. The document indicates that the judges had requested the AG to respond only to the first four of the six questions referred to, which are all related to Article 1(b) of the SPC Regulation, the definition of the active ingredient.

Direct impact: Statistics suggest AG opinions are followed by the ECJ in roughly 60-70% of preliminary reference proceedings. If the court follows AG Emiliou here, Halozyme’s SPC application in the Czech Republic fails. There is also evidence of broader divergence: Halozyme was granted the SPC by Belgium, Bulgaria, Spain, Italy, Cyprus, Luxembourg, Poland, and Slovenia, but it was denied by France, the Netherlands, and Sweden. In retrospect, one set of national rulings will be at odds with EU law, regardless of the ECJ’s conclusion.

Wider ramifications: The AG’s opinion favors legal certainty: if a company labels something an excipient, it is bound by that. Research-oriented pharma companies are unlikely to welcome this outcome, as it narrows SPC protection for substances that may perform real pharmacological work. The case sits squarely in the perennial tension of patent policy: enough protection to justify billion-dollar drug development investments, but not so much that generic entry is indefinitely delayed and healthcare systems bear the cost.