Big pharma giants Merck and Pfizer have added ASX small cap Immutep’s immunotherapy drug to a clinical trial program — and its shares are flying.

Immutep shares (ASX:IMM) jumped 10 per cent to 4.5c at the start of trade on Monday — its highest point since rebranding from its previous name of Prima BioMed.

Immutep announced a “clinical trial collaboration and supply agreement” with Merck and Pfizer.

The deal involves tests of Immutep’s drug candidate “eftilagimod alpha” — also known as IMP321 or just “efti”.

The two heavyweights will evaluate the combination of efti with an approved cancer drug called “avelumab” in patients with advanced tumours in a Phase I safety and efficacy trial.

“This novel combination regimen adds to our clinical development program to further evaluate the potential in different challenging cancers,” said Merck’s head of global clinical development, Alise Reicin.

Immutep shares (ASX:IMM) hit a year-high.

It is the second deal Immutep has announced this year with Merck. In March the company began evaluating the combination of efti with Merck’s KEYTRUDA drug — also to fight tumours.

It’s Merck third deal with an ASX-listed biotech this year.

The US giant earlier agreed to dish out $500 million in the acquisition of Viralytics. ASX-listed biotechs have seen a wave of attention from US drug companies this year.

Pfizer’s global product development boss Chris Boshoff said: “we look forward to collaborating with Immutep on this clinical trial collaboration, which will help us accelerate and advance treatment options that will potentially benefit more patients.”

Marc Voigt, Immutep chief, said the deal was affirmation of his company’s belief that “efti” has potential. It is a protein used in combination with other agents to amplify a patient’s immune response.

“We are delighted to have the opportunity to collaborate with Merck and Pfizer,” he said.

“We feel that this new collaboration, with these industry leaders, further supports our hypothesis that there is a potentially meaningful therapeutic benefit in combining eftilagimod alpha with a checkpoint inhibitor in the treatment of cancer and we look forward to the initiation of this clinical trial, planned for later this year, and the prospects of further clinical investigations.”