EX-99.1

Exhibit 99.1

LOGO

ASX/Media Release (Code: ASX: IMM; NASDAQ: IMMP)

IMMUTEP ANNOUNCES EUROPEAN PATENT GRANT FOR EFTILAGIMOD ALPHA IN

CHEMO-IMMUNOTHERAPY

SYDNEY, AUSTRALIA – 23 May 2019 – Immutep Limited (ASX: IMM; NASDAQ: IMMP) (“Immutep” or “the Company”), a biotechnology company developing novel immunotherapy treatments for cancer and autoimmune diseases, is pleased to announce the grant of a new patent (number 3089749) entitled “Combined Preparations for the Treatment of Cancer” by the European Patent Office.

The new patent protects Immutep’s intellectual property relating to combined therapeutic preparations comprising its lead active immunotherapy candidate eftilagimod alpha (“efti” or “IMP321”) and a chemotherapy agent. The chemotherapy agent is either a platinum-based anti-neoplastic agent, such as oxaliplatin or carboplatin, or a topoisomerase I inhibitor, such as topotecan.

Dr Frédéric Triebel, Immutep CSO and CMO, commented, “This new patent is important because platinum-based chemotherapy agents and topoisomerase I inhibitors continue to be commonly used forms of chemotherapy. In addition, the past couple of years has seen, for the first time, the marketing approval and adoption of first or second line combinations of chemotherapy and active immunotherapies for the treatment of advanced solid tumors.

As such, this new patent provides patent protection in Europe for a range of novel and highly relevant chemo-immunotherapies featuring efti that may be pursued in the future.”

The patent expiry date is 19 December 2034.

About Immutep

Immutep is a globally active biotechnology company that is a leader in the development of immunotherapeutic products for the treatment of cancer and autoimmune disease. Immutep is dedicated to leveraging its technology and expertise to bring innovative treatment options to market for patients and to maximize value to shareholders.

Immutep’s current lead product is eftilagimod alpha (“efti” or “IMP321”), a soluble LAG-3Ig fusion protein based on the LAG-3 immune control mechanism. This mechanism plays a vital role in the regulation of the T cell immune response. Efti is currently in a Phase IIb clinical trial as a chemoimmunotherapy for metastatic breast cancer termed AIPAC (clinicaltrials.gov identifier NCT02614833); a Phase II clinical trial referred to as TACTI-002 (Two ACTive Immunotherapies) to evaluate a combination of efti with KEYTRUDA^® (pembrolizumab) in several different solid tumours (clinicaltrials.gov identifier NCT03625323); a planned Phase I clinical trial referred to as INSIGHT-004 to evaluate a combination of efti with avelumab (clinical trials.gov identifier NCT03252938); and a Phase I combination therapy trial in metastatic melanoma termed TACTI-mel (clinicaltrials.gov identifier NCT02676869).