Japanese pharma giant Astellas and the University of California (UC) are heading to the Constitutional Court to try to block local pharma group Eurolab and Dis-Chem from making and distributing Enzutix, a generic of the expensive prostate cancer drug Xtandi, reports the Sunday Times.
Eurolab had obtained approval from the South African Health Products Regulatory Authority (SAHPRA) for the registration of Enzutix in January 2023. But when the University of California – whose scientists had developed the drug – found out, it joined its commercial partner Astellas in trying to get an undertaking from Eurolab not to proceed for the life of the patent.
The request was rejected by Eurolab, which approached the Commission of Patents, arguing on a legal technicality that the UC had not been entitled to apply for a patent for Xtandi in South Africa in the first place. The commission agreed with Eurolab, and UC and Astellas appealed against this decision at the Supreme Court of Appeal.
Earlier this year – in March – the SCA ruled in favour of UC and Astellas, but declined their application to interdict the sale of Enzutix pending the conclusion of the patent litigation.
The SCA said an interdict would not be appropriate because Enzutrix is a cheaper option than Xtandi, which, like many branded cancer medications, is financially unaffordable for most South Africans. According to Eurolab, one year’s supply of Xtandi costs nearly R361 000, while Enzutrix comes in at R299 407 – a saving of about R60 000.
In their papers in the Constitutional Court application, due to be heard this month, UC, which is also pursuing a multimillion-rand damages claim against Eurolab for patent infringement, and Astellas said about $1.5bn was spent developing Xtandi and Eurolab should not be allowed to use legal niceties to profit from their invention.
“It is in the public interest that research of this sort be incentivised through the grant of patents,” UC and Astellas argue.
Public interest
“It is equally in the public interest that patents are not made vulnerable to attack on highly technical grounds that have nothing to do with the merits of the invention; in respect of which there is no dispute between the interested parties; and which are advanced by firms for the sole purpose of trying to justify having stolen a march on other generics companies (that were waiting for the patent to expire) by distributing a generic of Xtandi while the patent was still in force,” they said.
Xtandi was developed at UC with grant support from the US’s National Institutes of Health and the US Army. The drug is used to treat men with prostate cancer that no longer responds to hormone therapy or surgical treatment.
Eurolab, citing the financial blow of a successful damages action by UC, plans to ask the Constitutional Court to rule that it did not infringe a patent.
“UC has instituted action for damages against Eurolab for patent infringement,” it says in an affidavit. “The validity of the patent is determinative of that claim. If the SCA judgment stands, Eurolab faces potential substantial monetary liability based on a patent that the Commissioner [of Patents] and the minority found to have been improperly obtained.
“This is not an academic question. Eurolab’s commercial interests, (that is) their right to sell a generic oncology drug, are directly at stake.”
UC and Astellas warned that offshore inventors might shy away from South Africa if the country’s patent laws allow Eurolab to triumph in the dispute.
“Most patents filed in South Africa do not originate from research carried out in this country. Merely to give the court some perspective in this regard, in 2025, 11 173 patents were filed in South Africa. Of those 11 173 patents, 8 910 (80%) were filed by foreign corporations.
“A very high percentage of patents owned by foreign corporations enter South Africa as PCT (patent co-operation treaty) national phase filings. The patent-in-suit followed that route.”
See more from MedicalBrief archives:
Victory for cancer victims as court allows generic medication
US university loses patent fight with SA generics company