Patent claims on synergistic application of cepharanthine, cabazitaxel and other taxane family members used in combination to treat primary, metastatic and chemotherapy-resistant prostate cancer

Expands on Company’s ‘pipeline in a pill’ strategy with cepharanthine in treating rare cancers

Toronto, Ontario – February 1, 2022 – PharmaDrug Inc. (CSE: PHRX) (OTCQB: LMLLF) (“PharmaDrug” or the “Company“), a specialty pharmaceutical company focused on the research, development and commercialization of controlled-substances and natural medicines such as psychedelics, cannabis and naturally-derived approved drugs, is pleased to announce that the Company has filed a US provisional patent application which details the novel synergistic combination of cepharanthine (PD-001) and cabazitaxel on prostate cancer growth inhibition and also sets forth claims related to the use of PD-001, cabazitaxel and/or other taxane family members used in combination to treat primary, metastatic and chemotherapy-resistant prostate cancer.

In 2021, the Company initiated a series of cancer screening studies aimed at uncovering therapeutic opportunities for cepharanthine when used alone or in combination with standard of care (SoC) chemotherapy drugs. Results from these studies revealed that prostate cancer was particularly responsive to cepharanthine, second only to esophageal cancer. Specifically, the top dose of cepharanthine examined inhibited growth of the prostate cancer cell line, 22Rv1 by 99.95% compared to the maximal growth inhibition noted for cisplatin of 95.46% and SoC, cabazitaxel of 96.63%. While the potency of cepharanthine on prostate cancer was notable in the context of other common chemotherapeutic agents, here the Company reports that the combination of cepharanthine plus cabazitaxel provided unexpectedly synergistic reduction in prostate tumor cell survival. A provisional US patent has now been filed to protect these findings and the Company plans to strategically build out and extend patent protection for PD-001 in the oncology space. Consistent with this, the Company has initiated in vivo prostate cancer model studies to examine the synergistic relationship between cepharanthine and cabazitaxel more closely. PharmaDrug will have one year post filing (January 26^th, 2023) to provide additional supportive data and to potentially modify its existing claim set based on new findings. During this time the Company plans to also continue with IND-enabling studies directed towards the use of cepharanthine for esophageal cancer; an indication that the Company’s PD-001 previously received orphan drug designation for.

Daniel Cohen, CEO and Chairman of PharmaDrug, commented, “We are extremely excited to continue to broaden the use case for PD-001 as a treatment for various cancers. While esophageal cancer continues to be our main focus with a goal to move towards an FDA clinical trial, we believe that cepharanthine will ultimately show a wider potential use in the treatment of cancers, specifically in combination with the current standard of care. We will continue to explore cepharanthine’s potential therapeutic relationship with existing standard of care chemotherapies.”

About PD-001 (Enteric-coated Oral Cepharanthine)

Cepharanthine is a natural product and an approved drug used for more than 70 years in Japan to successfully treat a variety of acute and chronic diseases. In clinical research, Cepharanthine has been shown to exhibit multiple pharmacological properties including anti-oxidative, anti-inflammatory, immuno-regulatory, anti-cancer, anti-viral and anti-parasitic effects^1,2. However, historically cepharanthine’s low oral bioavailability has represented a major obstacle to realizing its full clinical potential.

The Company is focused on advancing the clinical development of an improved and patented enteric-coated oral formulation of cepharanthine (PD-001) to treat responsive cancers and COVID-19. Compared to generic cepharanthine, PD-001 has been shown in rodent and non-rodent models to possess markedly superior oral bioavailability (more easily absorbed). These findings support the development of an orally administered formulation, and in so doing, removes the undesirable requirement for frequent intravenous dosing.

PD-001 for Cancer

PharmaDrug’s cancer program is based on cepharanthine’s known anti-cancer activities. Cepharanthine has been shown in multiple preclinical efficacy models to inhibit cancer cell proliferation, induce cancer cell apoptosis (death) and restore cancer cell sensitivity to multiple unrelated classes of chemotherapy. Multidrug resistance continues to represent a considerable clinical challenge. As such, preclinical cancer studies aimed at elucidating the mechanisms that underly chemoresistance; including the critical role drug efflux pumps play in this phenomenon by reducing the intracellular concentration of chemotherapeutic drugs, are of particular interest to PharmaDrug. Cepharanthine has been shown in preclinical studies to potently reverse chemoresistance by downregulating expression of ABCB1, the transcript of which codes for multidrug resistance protein 1, (MDR1, aka P- glycoprotein). Importantly, several prior in vitro and in vivo studies have shown that cepharanthine-mediated reductions in ABCB1 expression restores cancer cell sensitivity to a range of chemotherapeutics including taxanes, vinca alkaloids and platinum-based drugs^3-6. Collectively the two in vitro screening studies already completed by the Company, and those in vivo studies currently underway aim to identify and provide focus to novel opportunities in oncology by revealing optimal cancer cell types as a monotherapy and/or drug combinations and situations where PD-001 can prevent, lessen, or reverse chemoresistance, and provide additive or synergistic benefit to existing standard of care treatments. For reference to previous press releases related to PharmaDrug’s ongoing efforts in the oncology space please see previous press releases Nov 18, Oct 15, July 28, 2021. In addition to its ongoing investigations of PD-001 for prostate cancer, the Company plans to fully leverage the streamlined path to approval which comes by way of a recently granted FDA Orphan Drug Designation PD-001 for the treatment of esophageal cancer.

Potential of PD-001 to Treat Prostate Cancer

According to the American Cancer Society, in 2021 there were approximately 248,530 new cases of prostate cancer and about 34,130 deaths from prostate cancer in the United States, and it is the second leading cause of cancer death in American men. Metastatic prostate cancer is commonly treated using androgen deprivation therapy (ADT), including surgical or medical castration, but metastatic castration-resistant prostate cancer (mCRPC) commonly emerges⁷. The taxanes docetaxel and cabazitaxel are approved for the treatment of mCRPC, however resistance to taxanes is known to develop over time. Agents such as PD-001 which show synergistic benefit when combined with taxanes for the treatment of prostate cancer are sorely needed. The Company’s forthcoming in vivo studies are specifically designed to address the potential of PD-001 to overcome taxane-based chemoresistance in vivo.

About PharmaDrug Inc.

PharmaDrug is a specialty pharmaceutical company focused on the research, development and commercialization of controlled-substances and natural medicines such as psychedelics, cannabis and naturally-derived approved drugs. PharmaDrug owns 100% of Pharmadrug Production GmbH, a German medical cannabis distributor, with a Schedule I European Union narcotics license and German EuGMP certification allowing for the importation and distribution of medical cannabis to pharmacies in Germany and throughout the European Union. PharmaDrug owns 100% Sairiyo Therapeutics (“Sairiyo”), a biotech company that specializes in researching and reformulating established natural medicines with a goal of bringing them through clinical trials and the associated regulatory approval process in the US and Europe. Sairiyo is currently developing its patented reformulation of cepharanthine, a drug that has shown substantial third party validated potential for the treatment of Covid-19 and rare cancers. Sairiyo is also conducting R&D in the psychedelics space for the treatment of non-neuropsychiatric conditions. The Company also owns 100% of Super Smart, a company building a vertically integrated retail business with the goal to elevate the use of functional mushrooms, and psilocybin mushrooms where federally legal, as natural based medicines.

For further information, please contact:

Daniel Cohen, Chairman and CEO
dcohen@pharmadrug.co
(647) 202-1824

Caution Regarding Forward-Looking Information:

THE CANADIAN SECURITIES EXCHANGE HAS NOT REVIEWED NOR DOES IT ACCEPT RESPONSIBILITY FOR THE ADEQUACY OR ACCURACY OF THIS RELEASE.

This press release contains “forward-looking information” within the meaning of applicable securities legislation. All statements, other than statements of historical fact, included herein are forward-looking information. Generally, forward-looking information may be identified by the use of forward-looking terminology such as “plans”, “expects” or “does not expect”, “proposed”, “is expected”, “budgets”, “scheduled”, “estimates”, “forecasts”, “intends”, “anticipates” or “does not anticipate”, or “believes”, or variations of such words and phrases, or by the use of words or phrases which state that certain actions, events or results may, could, would, or might occur or be achieved. In particular, this press release contains forward-looking information in relation to: the development and commercialization of cepharanthine, the results of the Company’s research and development in the psychedelics space and the development of the Supersmart business . This forward-looking information reflects the Company’s current beliefs and is based on information currently available to the Company and on assumptions the Company believes are reasonable. These assumptions include, but are not limited to the ability of the Company to successfully execute on its plans for the Company and its affiliated entities; the ability to obtain required regulatory approvals and the Company’s continued response and ability to navigate the COVID-19 pandemic being consistent with, or better than, its ability and response to date.

Forward-looking information is subject to known and unknown risks, uncertainties and other factors that may cause the actual results, level of activity, performance or achievements of the Company to be materially different from those expressed or implied by such forward-looking information. Such risks and other factors may include, but are not limited to: general business, economic, competitive, political and social uncertainties; general capital market conditions and market prices for securities; the actual results of the Company’s future operations; competition; changes in legislation affecting the Company; the ability to obtain and maintain required permits and approvals, the timing and availability of external financing on acceptable terms; lack of qualified, skilled labour or loss of key individuals; risks related to the COVID-19 pandemic including various recommendations, orders and measures of governmental authorities to try to limit the pandemic, including travel restrictions, border closures, non-essential business closures, service disruptions, quarantines, self-isolations, shelters-in-place and social distancing, disruptions to markets, economic activity, financing, supply chains and sales channels, and a deterioration of general economic conditions; and a deterioration of financial markets that could limit the Company’s ability to obtain external financing.

A description of additional risk factors that may cause actual results to differ materially from forward-looking information can be found in the Company’s disclosure documents on the SEDAR website at www.sedar.com. Although the Company has attempted to identify important factors that could cause actual results to differ materially from those contained in forward-looking information, there may be other factors that cause results not to be as anticipated, estimated or intended. Accordingly, readers should not place undue reliance on forward-looking information. Readers are cautioned that the foregoing list of factors is not exhaustive. Readers are further cautioned not to place undue reliance on forward-looking information as there can be no assurance that the plans, intentions or expectations upon which they are placed will occur. Such information, although considered reasonable by management at the time of preparation, may prove to be incorrect and actual results may differ materially from those anticipated.

The Company’s securities have not been registered under the U.S. Securities Act of 1933, as amended (the “U.S. Securities Act”), or applicable state securities laws, and may not be offered or sold to, or for the account or benefit of, persons in the United States or “U.S. Persons”, as such term is defined in Regulations under the U.S. Securities Act, absent registration or an applicable exemption from such registration requirements. This press release shall not constitute an offer to sell or the solicitation of an offer to buy nor shall there be any sale of the securities in the United States or any jurisdiction in which such offer, solicitation or sale would be unlawful.

Forward-looking information contained in this press release is expressly qualified by this cautionary statement. The forward-looking information contained in this press release represents the expectations of the Company as of the date of this press release and, accordingly, are subject to change after such date. However, the Company expressly disclaims any intention or obligation to update or revise any forward-looking information, whether as a result of new information, future events or otherwise, except as expressly required by applicable securities law.

References:

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