Oncolytic viruses (OVs) have emerged as a remarkable non-to-low-toxic and non-invasive alternative to traditional cancer treatments. These relatively new cancer therapeutics are being increasingly explored by the pharmaceutical industry to benefit from their selectivity and potential to enhance existing medicines. Despite some early clinical trial successes, numerous obstacles impede the progress of this exciting therapeutic area. In this article, Kai Lipinski, Chief Scientific Officer at ReciBioPharm, delves into the challenges that OV developers face in pursuing project success and assesses potential resolutions to bring pioneering new treatments one step closer to launch.
A Need for New Cancer Treatments
Globally, cancer is estimated to cause 10 million deaths a year and accounts for every one in six fatalities.1 While traditional cancer treatments have improved survival rates, their efficacy and toxicity limitations amplify the need for alternatives or complementing treatment modalities. These include chemotherapy’s potentially disabling side effects, radiotherapy’s harm to surrounding healthy tissues and the invasive, often painful nature of surgery, underscoring the demand for innovation.
Promising approaches like chimeric antigen receptor T cell (CAR-T) and immune checkpoint blockade (ICB) therapies have limitations due to the immunosuppressive tumour microenvironment and cancer heterogeneity. Although proof-of-concept of CAR-T therapy for blood-related cancers is the reality today (CD19 target: Kymriah, Yescarta, Tecartus, Breyanzi; BCMA target: Abecma, Carvykti), successfully treating solid cancers is still to come. The potential to selectively target, infect and eliminate cancer cells while activating an immune response makes OVs a revolutionary prospect in the world of oncology. The roots of this therapy trace back to successful clinical trials as early as the 1950s.2
With an evolving understanding of molecular interactions, OVs are considered ideal candidates for combination therapies, especially when supporting traditional cancer treatments like immunotherapies. This combined approach allows for the targeting of a wider spectrum of tumours while enhancing therapeutic efficacy.3
The biopharmaceutical industry is enthusiastic about the transformative potential of OVs and is actively involved in developing new OV technologies to improve treatment outcomes. The burgeoning global OV market is projected to see a compound annual growth rate of 26.2% from 2021 to 2028, ultimately reaching $609.7 billion4. Despite a development pipeline containing over 100 OVs, their potential is yet to fully materialise into widespread commercial success. Currently, only one OV, T-VEC (Imlygic®), is approved for use in the US and there is one conditional approval in Japan (Delytact®; Daiichi Sankyo Company, Limited) for a regenerative medical product for treating malignant glioma – interestingly, both viruses are based on HSV-1.
Tackling OV Development Challenges
The push for more OVs to enter the market comes from various stakeholders. Patients with diverse cancer types would benefit directly from a broader range of potential oncology treatments while healthcare professionals would gain access to a more versatile set of treatment options. Developers, along with their investors, are eager to see OVs achieve success in the market.
However, navigating the path from preclinical development to commercialisation is challenging. OV developers embarking on this mission currently face a multitude of challenges despite the collective determination to make these promising therapies accessible to those in need.