ASX/Media Release Immutep s efti in combination with MSD s pembrolizumab shows encouraging antitumor activity in difficult to treat 2 nd line metastatic lung cancer patients All enrolled patients were 2 nd line metastati

Immutep s efti in combination with MSD s pembrolizumab shows encouraging antitumor activity in difficult to treat 2nd line metastatic lung cancer patients

SYDNEY, AUSTRALIA 30 March 2022 Immutep Limited (ASX: IMM; NASDAQ: IMMP) ( Immutep or

the Company ), a biotechnology company developing novel LAG-3-related immunotherapy treatments for cancer and autoimmune disease, announces new interim data

in 2nd line metastatic NSCLC from its Phase II TACTI-002 trial. The data was published in a poster presentation today at ESMO s European Lung Cancer

Congress (ELCC) 2022 in Prague, Czech Republic and is also available on the Company s website:

This part of TACTI-002, known as Part B, evaluates Immutep s lead product candidate, eftilagimod alpha

( efti or IMP321 ) in combination with MSD s KEYTRUDA (pembrolizumab) in a total of 36 patients with PD-L1 unselected 2nd line PD-X refractory metastatic NSCLC. The new data reflects the first interim results combining Stages 1 (23 patients) and 2 (13 patients) in 2nd line NSCLC.

Immutep CSO and CMO, Dr Frederic Triebel, noted: It is very encouraging to

see efti, in combination with pembrolizumab, showing an encouraging early overall survival rate of 73% at the six-month landmark, and promising interim disease control and tumour growth kinetics. The early

signs are supportive that efti may boost the patient s immune system to enable pembrolizumab to work more effectively in these patients with advanced lung cancer, while being safe and well tolerated.

TACTI-002 Principal Investigator, Dr Matthew G. Krebs of The University of Manchester and The Christie NHS

Foundation Trust, said: These interim results show an encouraging disease control rate of 36.1%, with 26% of patients being progression free at the 6-month landmark. These patients are a challenging

population to treat, having progressed after previous lines of immunotherapy or chemo-immunotherapy and have limited options available for further treatment. So, it is pleasing to see the potential that efti in combination with pembrolizumab has to

provide meaningful benefit in this patient group.

Condition of the patients as they entered the trial

A total of 36 patients were enrolled and treated. Patients were advanced in their disease. They had progressed after prior standard of care treatment with

either anti-PD-(L)1 mono therapy (28%) or a combination of chemotherapy and anti-PD-(L)1

therapy (72%) and are referred to as PD-X refractory. Disease progression was confirmed by two consecutive CT-scans at least four weeks apart, eliminating the

possibility of pseudo-progressions.1 The majority of patients (69%) had a PD-L1 tumour proportion score (TPS) of less than 50% at baseline, making them

generally less likely to respond to anti-PD-(L)1 therapy.

Findings data cut-off date 21 January 2022

Table 1 TACTI-002 Interim Results for Part B of TACTI-002

The combination of efti plus pembrolizumab is safe and well-tolerated, continuing efti s good safety profile to date and compares favourably to standard

of care chemotherapy options.

interim data from the TACTI-002 study shows that efti in combination with pembrolizumab is demonstrating encouraging early signs of antitumour activity in

2nd line confirmed PD-X refractory, NSCLC patients.

More mature data from the 2nd line

NSCLC cohort is planned to be presented later this year, along with other data from the TACTI-002 trial.

TACTI-002 (Two ACTive Immunotherapies) is being

conducted in collaboration with Merck & Co., Inc., Kenilworth, NJ, USA (known as MSD outside the United States and Canada). The study is evaluating the combination of eftilagimod alpha (efti) with MSD s KEYTRUDA (pembrolizumab) in patients with second line head and neck squamous cell carcinoma or non-small cell lung cancer in first and second line.

The trial is a Phase II, Simon s two-stage, non-comparative, open-label, single-arm, multicentre clinical study that is taking place in study centres across Australia, Europe, and the US.

Patients participate in one of the following:

TACTI-002 is an all-comer study in terms of PD-L1 status, a well-known predictive marker for response to pembrolizumab monotherapy especially in NSCLC and HNSCC.

More information about the trial can be found on Immutep s website or on ClinicalTrials.gov (Identifier:

Immutep is a globally active biotechnology company that is a leader in the development of LAG-3 related

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 is listed on the Australian Securities Exchange (IMM), and on the NASDAQ (IMMP) in the United States.

Immutep s current lead product candidate is eftilagimod alpha ( efti or IMP321 ),

a soluble LAG-3 fusion protein (LAG-3Ig), which is a first-in-class antigen presenting

cell (APC) activator being explored in cancer and infectious disease. Immutep is also developing an agonist of LAG-3 (IMP761) for autoimmune disease. Additional LAG-3

products, including antibodies for immune response modulation, are being developed by Immutep s large pharmaceutical partners.

can be found on the Company s website www.immutep.com or by contacting:

Australian Investors/Media:

Catherine Strong, Citadel-MAGNUS

+1 (212) 915.2564; tim@lifesciadvisors.com

This announcement was authorised for release by the Board of Immutep Limited.

Immutep Limited, Level 33, Australia Square

264 George Street, Sydney NSW 2000