Immutep Limited (NASDAQ:IMMP) shares are surging on Wednesday, up 100%, following the announcement that the company received FDA orphan drug designation for its product, eftilagimod alfa, in treating soft tissue sarcoma.

Immutep is a clinical-stage biotechnology company developing novel immunotherapies for cancer and autoimmune diseases.

The company is focused on therapeutics related to Lymphocyte Activation Gene-3 (LAG-3), and its diversified product portfolio harnesses LAG-3’s ability to stimulate or suppress the immune response.

The FDA’s orphan drug designation program encourages the development of therapies for rare diseases, providing benefits such as regulatory support and potential market exclusivity.

The designation for eftilagimod alfa highlights the company’s commitment to advancing its therapies in oncology.

Immutep Halts TACTI-004 Phase 3 Trial

In March, the company halted the TACTI-004 Phase 3 trial based on a review of safety and efficacy data, leading to an orderly wind-down of the study and a reassessment of capital allocation priorities.

The TACTI-004 trial was evaluating the company's lead drug, eftilagimod alfa, in combination with Merck & Co. Inc.'s (NYSE:MRK) Keytruda (pembrolizumab) and chemotherapy as first-line therapy for advanced/metastatic non-small cell lung cancer (NSCLC).

Efti is under evaluation for a variety of solid tumors, including NSCLC, as well as head and neck squamous cell carcinoma (HNSCC), soft tissue sarcoma, and breast cancer.

In May 2025, Immutep shared additional data from the investigator-initiated INSIGHT-003 trial of triple combination therapy in front-line NSCLC consisting of efti administered in conjunction with Keytruda and chemotherapy (carboplatin and pemetrexed).

Immunosuppressive Effects Observed

In December 2025, Immutep shared an update from the placebo-controlled, double-blind first-in-human Phase I study in healthy participants evaluating IMP761, a first-in-class LAG-3 agonist antibody for autoimmune diseases.

The single-ascending dose escalation portion of the trial completed the 2.5 and 7 mg/kg dosing levels of IMP761 with continued positive safety and efficacy data.

IMP761 was tolerated well with no treatment-related adverse reactions beyond mild intensity.

Analyst Consensus & Recent Actions: The stock carries a Buy Rating with an average price target of $5.50. Recent analyst moves include:

  • Citizens: Downgraded to Market Perform (March 13)
  • Baird: Downgraded to Neutral (Lowers Target to $1.00) (March 13)

IMMP Price Action: Immutep shares were up 97.24% at $1.02 at the time of publication on Wednesday, according to Benzinga Pro data.

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