AAP Finance

Biotech shares plunge after lung cancer drug's failure

Mar 13, 2026

A scientist works in a medical la — A biotech company's share price plunged after the failure of a lung cancer treatment drug. -AAP Image

Shares in an leading ASX-listed biotech have lost nearly all of their value after its lead drug candidate failed as a lung cancer treatment.

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Immutep shares had plunged 90 per cent to 4 cents near midday on Friday, taking its market capitalisation from over $500 million to just $52 million - far less than the value of Immutep's bank account.

The company reported having a balance of $99 million in cash and cash equivalents at the end of 2025 and received a $29.9 million licensing payment in January from Indian drug company Dr Reddy's.

Friday's nosedive occurred after Immutep said it was abandoning a phase III trial investigating the use of its injection known as "efti" to treat non-small cell lung cancer, the most common type of lung cancer.

An independent oversight committee had recommended the trial be wound down after an interim "futility analysis" found it was unlikely to be successful.

There had been over 378 patients from 25 countries with advanced lung cancer enrolled in the study, which will now be discontinued with appropriate follow-up care given to patients in accordance with regulatory and ethical obligations, Immutep said.

The plan had been for the study to enrol around 756 patients to see whether efti could work synergistically with Merck's Keytruda to enhance the effectiveness of that blockbuster drug, a so-called miracle cancer cure with $43 billion in sales in 2025.

"We are very disappointed and surprised with the outcome of the futility analysis, in light of efti's performance in every other clinical trial," said Immutep CEO Marc Voigt.

Immutep said it would continue its clinical trials evaluating efti as a treatment for head and neck squamous cell carcinoma, soft tissue sarcoma and breast cancer.

Discontinuing the study will extend Immutep's cash runway well beyond its previous forecast mid-2027, the company said.

Immutep's biggest shareholder is Regal Funds Management, which owns 13.8 per cent of the company.

Regal also posted a nine-figure loss in 2025 after the collapse of another ASX-listed biotech in which it had invested.

Regal wrote off its entire 30 per cent stake in Opthea in early 2025, after the company's potential treatment for retinal disease failed in a clinical trial. The shares haven't traded in months.

After that loss, Regal chief investment officer Philip King told investors that "stocks with event driven binary outcomes will be limited to a far smaller weighting within our strategies going forward."