CSE: DTC  FSE: DTC  USOTC: DTCFF 

Vancouver, BC, Canada, October 10^th, 2023 - Defence Therapeutics Inc. (“Defence” or the “Company”), a biotechnology company developing various products for the immune-oncology vaccines and drug delivery technologies, is pleased to announce the publication of a peer-reviewed study on the anticancer properties of its unconjugated Accum®, one of Defence’s product designed notably to treat established T-cell lymphoma. The study, which was published in the prestigious journal of Cancer Science, is entitled, "Intratumoral administration of unconjugated Accum® impairs the growth of pre-established solid lymphoma tumors", and can be directly accessed at the following address:

http://doi.org/10.1111/cas.15985

The urgent need for novel anticancer therapeutics fuels active research in this field. From that perspective, Accum® holds many advantages over molecules discovered by high throughput screening because: i) it was rationally designed to break down endosomal membranes and hence has a known initial function, ii) the chemical structure of the molecule could be easily modified to generate several Accum® variants, iii) it can be easily linked to antibodies as an in situ cleavable anticancer molecule (to increase its specificity), and iv) it is highly versatile, as it targets a common pathway(s) relevant to any, if not most, cancer indication.

"This study presents insights of how the unconjugated Accum® molecule disrupts multiple intracellular events in cancer cells leading to its implosion. The recruitment of important immune T cells (CD4 and CD8) highlights another very important concept as it clearly shows that the molecule attacks cancer cells on two fronts: by inducing cell death and by alerting the immune system of a danger to fight" says Dr. Rafei, the Chief Scientific Officer of Defence Therapeutics.

The key highlights of the Accum®^{study are:}

• The molecule induces cell death of various cancer cell lines (T-cell lymphoma, colon, melanoma and breast).
• Accum® triggers the intracellular production of reactive oxygen species and disrupts endosomal membranes.
• Following contact with Accum®, cancer cells die through a process called immunogenic cell death.
• The Accum® effect required both CD4 and CD8 T cells (important in fighting cancer).
• Intratumoral administration of Accum® synergises with common immune-checkpoint inhibitors leading to efficient tumor growth control.

“This prestigious peer-reviewed publication provides an important validation of the antitumoral properties of unconjugated Accum®. It also opens up a new line of investigation where more potent Accum® variants could be tested as an anti-cancer injectable,” said Mr. Plouffe, Chief Executive Officer of Defence Therapeutics.

In summary, unconjugated Accum® could be used as an anti-cancer molecule. The triggered effects are very interesting and unexpected as the induction of immunogenic cell death brings an additional immune component to the equation, which may turn a "cold" into a "hot" tumor with increased infiltration of immune cells as shown in the published study.

About Defence:

Defence Therapeutics is a publicly-traded biotechnology company working on engineering the next generation vaccines and ADC products using its proprietary platform. The core of Defence Therapeutics platform is the ACCUM®^{technology, which enables precision delivery of vaccine antigens or ADCs in their intact form to target cells. As a result, increased efficacy and potency can be reached against catastrophic illness such as cancer and infectious diseases.}

For further information:

Sebastien Plouffe, President, CEO and Director

P: (514) 947-2272

Splouffe@defencetherapeutics.com

www.defencetherapeutics.com

Cautionary Statement Regarding “Forward-Looking” Information

This release includes certain statements that may be deemed "forward-looking statements". All statements in this release, other than statements of historical facts, that address events or developments that the Company expects to occur, are forward-looking statements. Forward-looking statements are statements that are not historical facts and are generally, but not always, identified by the words "expects", "plans", "anticipates", "believes", "intends", "estimates", "projects", "potential" and similar expressions, or that events or conditions "will", "would", "may", "could" or "should" occur. Although the Company believes the expectations expressed in such forward-looking statements are based on reasonable assumptions, such statements are not guarantees of future performance and actual results may differ materially from those in the forward-looking statements. Factors that could cause the actual results to differ materially from those in forward-looking statements include regulatory actions, market prices, and continued availability of capital and financing, and general economic, market or business conditions. Investors are cautioned that any such statements are not guarantees of future performance and actual results or developments may differ materially from those projected in the forward-looking statements. Forward-looking statements are based on the beliefs, estimates and opinions of the Company's management on the date the statements are made. Except as required by applicable securities laws, the Company undertakes no obligation to update these forward-looking statements in the event that management's beliefs, estimates or opinions, or other factors, should change.

Neither the CSE nor its market regulator, as that term is defined in the policies of the CSE, accepts responsibility for the adequacy or accuracy of this release.