Former minister Ronald Plasterk has ruled himself out as a potential prime minister in the next Dutch government after questions were raised about his handling of a patent for a cancer medicine.

Plasterk, 67, was never officially nominated for the job, but was widely tipped to be PVV leader Geert Wilders’s choice to head the cabinet that is being formed by a quartet of right-wing parties.

Last week allegations that he claimed sole patent rights for a cancer vaccine that was developed in association with Amsterdam’s UMC hospital centre resurfaced, leading to fresh questions about his integrity.

Plasterk sold his biotech company, Frame Therapeutics, to German pharmaceutical firm CureVac shortly afterwards for €32 million. The patents for the cancer vaccine were valued at €6 million.

He is also the subject of an official complaint for documentary fraud after an Amsterdam-based lawyer claimed he had misled the tax office by registering his company as a micro-enterprise.

“Futile”

Wilders, as leader of the largest party in the four-way coalition, will now have to find an alternative candidate to lead the new government, but it is far from clear who he can turn to instead.

Plasterk said in a statement quoted in the Telegraaf that he was “no longer available” for the position of prime minister, while dismissing the allegations against him as “essentially untrue” and “futile”.

“Recently reports have appeared in which my integrity was called into question and which would have impeded my ability to perform my duties as prime minister had I been appointed, even though they are incorrect,” he wrote.

“The accusations are essentially untrue and otherwise futile. I have complete integrity and was prepared to have it comprehensively tested by the formateur [lead negotiator] and his advisers.

“I am no longer available as leader of the cabinet. I thank the many people who have expressed their confidence in me.

“Finally, I have every confidence that this cabinet, which has good plans for the country, will take shape.”