Sipuleucel-T (Dendreon Corporation)

Chinese biotech WestGene announced an FDA approval for its mRNA therapeutic cancer vaccine. Credit: aslysun via Shutterstock. The US Food and Drug Administration (FDA) has approved an mRNA therapeutic cancer vaccine developed by China-based biotech WestGene. This decision makes the vaccine the world’s first approved mRNA therapeutic vaccine to treat Epstein Barr (EB)-virus-related cancers. The approval was based on results from investigator-initiated trials that evaluated the vaccine in patients with nasopharyngeal carcinoma (NPC) and natural killer T cell lymphoma. EB virus is a part of the herpesvirus family and spreads primarily through bodily fluids. The illness infects more than 90% of the global adult population but does not always lead to cancer, as detailed by Cancer Research UK. The virus has been linked with NPC, gastric cancer, lung cancer and other diseases. In a 10 May press release, WestGene highlighted liver cancer, oesophageal cancer, breast cancer and the aforementioned diseases as potential future indications for the vaccine. The Chinese company has a pipeline that includes four infectious disease vaccines, seven anti-tumour immunotherapies, and three gene editing treatments amongst other therapies. See Also: Formosa and Tabuk sign deal for FDA-approved ophthalmic suspension Four ways the vaccine rush will define infectious disease trends for CROs in 2024 In 2010, the FDA approved Dendreon Pharmaceutical’s prostate cancer prophylactic Provenge (sipuleucel-T) as the first marketed therapeutic cancer vaccine. Since its approval, other therapeutic cancer vaccines have entered the US market, with eight being available in the US, according to GlobalData. GlobalData is the parent company of Pharmaceutical Technology. In 2021, Pfizer and BioNTech gained the first-ever FDA approval for an mRNA vaccine with Comirnaty (BNT162b2) as a preventative measure against Covid-19. Since this milestone, several preventive and therapeutic mRNA vaccines have been in development for a wide range of conditions. Some pharmaceutical companies are using the mRNA approach to develop vaccines for other infectious diseases such as respiratory syncytial virus (RSV), Influenza A, Influenza B and cytomegalovirus while companies, including Moderna , Curevac , and Cartesian Therapeutics, are developing therapeutic mRNA vaccines for treating different cancers.

On the heels of early, but promising, cancer vaccine data released at this year’s American Association for Cancer Research (AACR) annual meeting, Corner Therapeutics on Thursday  detailed how its two technology platforms can supercharge the modality. The biotech also announced a $54-million series A that will help put its first vaccine to the clinical test next year. In addition to the financing, which was led by Ziff Capital Partners and saw participation from Cockrell Interests, Tanis Ventures, and Sandia Holdings, Corner also has grant funding from the Bill & Melinda Gates Foundation to apply its technology to infectious diseases, including HIV, influenza and COVID-19.The company’s tech is designed to elicit a strong, long-lasting immune response by activating dendritic cells – the so-called “apex regulators” of the immune system because they are the only cell type that can stimulate new T cell responses. While the idea of dendritic cell-associated cancer vaccines is not new, Corner has come a long way from the earliest iteration at Dendreon Therapeutics and the long and messy history of its Provenge (sipuleucel-T). The FDA approved the immunotherapy in 2010 to treat prostate cancer, but at the time it was seen as an expensive and difficult-to-use treatment – with questionable efficacy – and failed to be a commercial success, leading to a bankruptcy declaration from Dendreon in 2014. The company has since managed to turn its business around and began earning a profit in 2018. For more, see ViewPoints: Now officially walking, Dendreon sets its sights on running. Powering up dendritic cellsThere are two major differences between Dendreon and Corner’s vaccine work, CEO  Steven Altschuler told FirstWord. He previously was CEO of the Children’s Hospital of Philadelphia from 2000 to 2015 and also co-founded Spark Therapeutics, serving as chair until Roche acquired the gene therapy company for $4.3 billion in 2019.First, the biotech’s products will be in vivo, while Provenge is an ex vivo therapy that sources dendritic cells from a patient and exposes them to antigens before readministration. And second, Corner’s first platform is intended to promote a heightened state in dendritic cells – not just activated, but “hyper”activated. Dendritic hyperactivation was first discovered more than eight years ago by scientific co-founder Jonathan Kagan, a professor of paediatrics at Harvard Medical School. He found that when dendritic cells are in this state – triggered when the body sends both “infection” and “tissue damage” signals – stronger CD8+ T cell responses are generated, thanks to a pair of cellular processes that don’t occur during normal activation.Within dendritic cells, inflammasomes form and secrete IL-1β, a cytokine known to generate new, and reactivate existing, memory T cells. Additionally, a mass migration of dendritic cells to the lymph nodes – the primary T cell meet-up zone – is triggered. “These extra stimuli that we can apply makes a world of difference in terms of generating cellular immunity,” Altschuler said.A protein antigen-based vaccine developed with Corner’s hyperactivation platform will comprise three components: a proprietary oxidised lipid to send the “damage” signal, a TLR7/8 agonist to activate the “infection” signal, and the disease antigens. According to Altschuler, the modality is antigen-agnostic and can use neoantigens sourced from a cancer patient to create a personalised treatment, or incorporate a viral antigen for an off-the-shelf infectious disease vaccine. A STINGing immune boostIn tandem, Corner is developing a catalytic adjuvant technology intended to boost the power of mRNA-based vaccines by activating a well-known immune pathway: STING.While STING agonists have struggled to show efficacy in clinical cancer trials, Altschuler said Corner’s tactic causes continuous pathway activation.The company has developed an mRNA-encoded enzyme that reacts with naturally occurring cellular DNA to catalyse the formation of cGAMP, which is a precursor of the STING pathway.“What we have found is that this mechanism induces very profound antigen-specific T cell responses,” Altschuler said, adding that the platform is “very flexible and in effect, antigen-agnostic.”As an example of the platform’s potential power, Altschuler pointed to mRNA-based cancer vaccines already in development, such as Moderna’s mRNA-4157 (V940). At AACR, the biotech shared new data showing that the individualised neoantigen therapy, in combination with partner Merck & Co.’s anti-PD-1 antibody Keytruda (pembrolizumab), led to a response rate of 27.3% in 22 patients with unresectable, metastatic HPV-negative head and neck squamous cell cancer (HNSCC).If Corner’s catalytic adjuvant technology was incorporated into an mRNA-based vaccine, “we would expect our platform to enhance the efficacy of those vaccines because of this much better T cell response,” Altschuler said, which could in turn confer longer immunity.