Press Release

27 November 2017

Immunicum Announces Positive Preliminary Results from Proof-of- Concept Animal Study Testing Combination of Ilixadencel and Checkpoint Inhibitors

Immunicum AB (publ; First North Premier: IMMU.ST), a biopharmaceutical company advancing a novel, immune-priming cancer treatment against a variety of solid tumors, today announced preliminary proof-of-concept results from preclinical studies evaluating the potential improvement of anti-tumor effect when combining lead candidate ilixadencel with an anti-PD-1 checkpoint inhibitor (CPI).

• In an in vivo mouse model of a solid tumor cancer, the survival at Day 24 was 50% in mice treated with the combination of ilixadencel and a CPI, 30% for those mice treated with ilixadencel only and 0% for those receiving CPI only (see survival table below).

• In in vitro (cell culture) experiments with human immune cells and ilixadencel, addition of a CPI led to increased production of interleukin-2 and interleukin-1-beta, both important factors for immune cell activation and tumor cell killing.

The data is supportive of Immunicum's recently announced clinical development plan. More detailed and final study results will be presented in a peer-reviewed format following the completion of the studies.

"Although it is important to note that these preliminary preclinical data cannot be directly extrapolated to patients, the results scientifically support our decision to prioritize the combined ilixadencel-CPI treatment study in multiple indications in the updated clinical development plan," said Alex Karlsson-Parra, CSO of Immunicum.

In vivo tumor model:
To investigate the impact of combining ilixadencel with CPIs, an animal study was designed using an established mouse model for testing anti-cancer drug combinations. Three groups of mice with inoculated tumors were treated with either the CPI alone, the mouse surrogate for human ilixadencel (m-ilixadencel) alone, or a combination of m-ilixadencel and the CPI. Treatment started six days after subcutaneous tumor inoculation. Two doses of m-ilixadencel were injected intratumorally five days apart while the CPI continues to be injected intraperitoneally two times per week during the whole study period. The study is being conducted at Charles River Laboratories (Morrisville, USA).

The result to date indicate an enhanced anti-tumor effect when m-ilixadencel is combined with a CPI.

Survival after start of treatment (n=10 per group):

Neither treatment group displayed any tolerability issues during treatment

In vitro experiments:
In the in vitro experiments, a CPI was added to cell cultures in which ilixadencel had been mixed with human allogeneic immune cells, mimicking the interaction between intratumorally injected ilixadencel and the patient's recruited immune cells. The addition of the CPI to the cell culture increased the production of two key pro-inflammatory factors:

• Interleukin-2, known to enhance NK cell-mediated killing of tumor cells; and
• Interleukin-1-beta, which plays a central role in dendritic cell-mediated activation of antigen-specific cytotoxic CD8+ T cells.

"As we move toward the initiation of the multi-indication Phase 1/2 combination study planned in 2018, we are pleased to continue to expand the data supporting ilixadencel's potential as a backbone component of state of the art combination cancer therapies," said Carlos de Sousa, CEO of Immunicum.

Ilixadencel has up to now been tested in over 85 patients and is currently in clinical development in an ongoing Phase II trial in renal cell carcinoma (MERECA) as well as a Phase I/II study in gastrointestinal stromal tumors. Furthermore, ilixadencel has successfully completed Phase I/II studies in renal cell carcinoma and hepatocellular carcinoma with a favorable safety profile and signs of tumor-specific immune activation in the majority of patients.

About ilixadencel
Ilixadencel cell therapy product (formerly known as INTUVAX^®) is an off-the-shelf cancer immune primer, developed for the treatment of solid tumors. Its active ingredient is activated allogeneic dendritic cells, derived from healthy blood donors. Intratumoral injection of these cells is expected to lead to an inflammatory response which in turn leads to tumor-specific activation of the patient's cytotoxic T-lymphocytes.

The information is information that Immunicum is obliged to make public pursuant to the EU Market Abuse Regulation. The information was submitted for publication, through the agency of the contact persons set out above on 27 November 2017, at 8:00 a.m. CET.

For more information, please contact:

Carlos de Sousa, CEO, Immunicum
Telephone: +46 (0) 31 41 50 52
E-mail: info@immunicum.com

Investor Relations Sweden

Helena Stångberg
Hallvarsson & Halvarsson
Telephone: + 46 709 71 12 53
E-mail: ir@immunicum.com

Investor and Media Relations EU/US

Gretchen Schweitzer
Trophic Communications
Telephone: +49 172 861 8540
E-mail: ir@immunicum.com

The Company's Certified Adviser is Redeye AB
Telephone: +46 (0)8 545 013 30
www.redeye.se