Immutep Quarterly Activities Report Q4 FY23

Media Release

Late-stage & registrational trial progress:

• TACTI-004 Phase III - Positive feedback received from US FDA for planned registrational trial in 1st line non-small cell lung cancer (1L NSCLC)
• TACTI-003 Phase IIb – Randomised study in 1st line head & neck squamous cell carcinoma (1L HNSCC) has reached ~91% patient recruitment and top-line results expected in H2 of CY2023
• AIPAC-003 Phase II/III - First patient dosed in metastatic breast cancer trial

Positive eftilagimod alpha (efti) clinical results in TACTI-002 and INSIGHT-003 trials:

• TACTI-002 Phase II evaluating efti + KEYTRUDA (pembrolizumab) led to excellent initial Overall Survival (OS) benefit of 25 months in 1L NSCLC patients with >1% PD-L1 TPS; more mature data in H2 of CY2023
• Final results in 2L HNSCC from TACTI-002 presented at ASCO 2023 showed promising response rates, overall survival, and durable responses including a Complete Response in patient with negative PD-L1
• INSIGHT-003 Phase I evaluating efti + KEYTRUDA + doublet chemo achieved 67% response rate and 91% disease control rate in 1L NSCLC, despite 81% of patients having low or negative PD-L1 expression

Efti trial expansion:

• INSIGHT-005 - Regulatory approval to commence the investigator-initiated trial in urothelial carcinoma
• EFTISARC-NEO - Investigator-initiated trial commenced in soft tissue sarcoma

Well financed:

• Strong cash position of $123.4m, following A$80m capital raise for registrational and late-stage trials of efti and potentially a first-in-human trial for IMP761; extends cash runway to early CY2026

SYDNEY, AUSTRALIA, July 31, 2023 (GLOBE NEWSWIRE) -- Immutep Limited (ASX: IMM; NASDAQ: IMMP) ("Immutep” or “the Company”), a biotechnology company developing novel LAG-3 related immunotherapy treatments for cancer and autoimmune diseases, provides an update on the ongoing development of its product candidates, eftilagimod alpha (efti) and IMP761 for its fiscal fourth quarter ended 30 June 2023 (Q4 FY23).

EFTI DEVELOPMENT PROGRAM FOR CANCER

TACTI-002 (KEYNOTE-PN798) Phase II clinical trial evaluating efti + KEYTRUDA (pembrolizumab):

• 1st line Non-Small Cell Lung Cancer (1L NSCLC)

Meaningful long-term survival was reported in from Immutep’s TACTI-002 (Two ACTive Immunotherapies) trial in May. An initial median Overall Survival (mOS) of 25 months was achieved in 1L NSCLC patients with >1% PD-L1 TPS (Tumour Proportion Score), a key area of focus for future clinical development with FDA Fast Track designation granted for efti and pembrolizumab in this patient population. Encouragingly, the initial mOS of 25.0 months for this chemo-free combination exceeds the reported rates for patients with the same PD-L1 TPS of >1% from registration trials of anti-PD-1 monotherapy (16.4-month mOS) and combinations of anti-PD-1 with chemotherapy (15.8-to-23.3-month mOS) or with anti-CTLA-4 (17.1-month mOS).