What is your vision for PDS Biotech and overarching goal in the fight against cancer?

Even though I started out in the industry as a scientist, I always had significant interest in how the larger business operated. Finding the most successful ways to transition from development to commercialization has been my bread and butter for many years so when we founded PDS Biotech, all this former knowledge and experience leading biotech organizations really paid off. One of the key things that I have learned throughout my career is that expertise is absolutely crucial for the success of a company. As a result, we have built a team of highly skilled staff with the goal to develop novel immunotherapy products in oncology. We aim to revolutionize cancer treatment through simple, more effective drugs and more tolerable therapies. 

Unfortunately, cancerous cells have multiple ways of surviving so the future of cancer cures will be combination therapies. Moreover, safety is going to become a central pillar in all future treatments so we believe that the promising results we have seen with our platform (Versamune®) can push us forward in this field. With so many companies developing viable gene and immunotherapy options, the next decades will hopefully bring important developments that will turn cancer into a chronic rather than a deadly disease. 

What would be some of the most important technologies that you managed to develop through your oncology programs?

Immunotherapy has come a long way in the past 20 years, especially with the approval of checkpoint inhibitors. However, the ability to induce the right type of killer T cells in a patient's body is still a significant limitation, since finding both the right potency and quantity are vital parameters. Across our trials, we have seen an enhancement of the therapeutic benefit when these killer T cells are being effectively generated in the patients. Moreover, overcoming the tumor's immunosuppressive mechanisms has also proved challenging since the cancers are often able to hijack some of the body’s natural regulatory mechanisms such as the immune checkpoints to evade the body's defense mechanisms. Despite how widely used checkpoint inhibitors are today, they still work in a very small percentage of cancer patients. For example, in head and neck cancer, the percentage of patients who have significant tumor shrinkage is less than 20%. In order to overcome this issue, we are combining our Versamune® platform technology with our novel tumor-targeting IL-12 therapy (PDS0301) which has shown the potential to more broadly overcome the immune suppression when combined with a checkpoint inhibitor. This combination had a response rate of 88% in CPI naïve subjects as shown by the National Cancer Institute trial in patients with anal, cervical, head and neck, vaginal and vulvar cancers.

For 29 patients who, historically, had a median survival of only three to four months to live, we managed to extend this period to 21 months, with a response rate of 63% in the group of patients who received the most effective doses from the current reported standard of less than 10%. 

There still is some skepticism around the T cell activating platforms, so our goal is to show that our products actually work even in difficult cases (e.g., tumors larger than 5 centimeters) in combination with other therapies. The preliminary data is extremely promising in this sense. In the MD Anderson-led cervical cancer trial for our lead product PDS0101, we have seen how the circulating tumor DNA in the blood that was observed after radiation and chemotherapy were brought down to zero. Eight out of the nine patients that were given PDS0101 therapy had complete responses 170 days post treatment, which translated into zero evidence of cancer. These findings showed a clear correlation between the induction of the right kind of killer T cells and the ability to eliminate cancer cells. Since durability is the most important aspect of cancer therapies, we have also shown the ability of our Versamune® based immunotherapies to generate T cells that retain a memory of the target cancer, where the T cells don’t just recognize the target but can also remember it and continue to fight it over a sustained period of time. 

Safety of combination cancer therapies is also receiving some attention. KEYTRUDA® (pembrolizumab) on its own is reported to have around a 17% severe adverse event rate, but the first 43 patients who have been evaluated on the combination with our therapy (PDS0101) showed no sign of this grade 3 or 4 toxicity level. Some checkpoint inhibitor side effects are autoimmune, but adding PDS0101 to the checkpoint inhibitors may result in a more uniform population of T cells that are specifically trained to seek out and attack only the cancer.  We are continuing to study these effects.

In what ways will your infectious diseases pipeline impact vaccine protocols?

The infectious diseases pipeline profits from the leeway of the T cells approach and adds in the traditional neutralizing antibodies side. By generating T cells that recognize conserved and non-mutated regions of the virus, we are aiming to develop vaccines that not only generate neutralizing antibodies but that also identifies non-mutating regions, thus allowing the T cells to kill the virus. Dr. Ted Ross is a leader in the field of influenza and he designed computer-generated influenza antigens (proteins) - which we are now combining with our Infectimune™ technology to obtain a better immunological response for a universal flu vaccine. In tests, mice that were infected with a lethal dose of the H1N1 virus had a 100% survival rate with our technology, while using only the protein itself, 30% survived but all of them got extremely sick. 

How do you perceive the current appetite of investors in the small to medium biotech sector?

The last 18 months have been a tough environment for biotech, but since we became a public company, we have managed to meet all the company goals that we have set. As a result, around November we started to see renewed interest in our programs from the investment community. For a company with four Phase 2 human clinical trials, we had an extremely low burn rate, partly due to our partnership with leading cancer institutions. These harsh times are going to act as a reset of the entire industry and the companies that have strong science programs and are efficient in managing their finances will definitely be able to attract investors.