Australian firm ESFAM Biotech is hoping to find a commercial destination for its sole veterinary candidates, allowing it to focus on its human health business. IHS Markit’s head of animal health Joseph Harvey spoke to the company’s Philip Crealy at the recent Animal Health Innovation Asia forum about the benefits of its pipeline.

ESFAM Biotech has developed a new class of viral entry inhibitor as treatments for porcine reproductive and respiratory syndrome (PRRS). The firm has two small molecule candidates for the prominent viral disease in pigs. Philip Crealy, the company’s head of external relationships, said: “The two lead compounds have shown potent anti-PRRS activity and efficacy against well-validated models including highly prevalent and resistant strains including NADC-20, VR2332 and Lelystad.”

Mr Crealy is hoping the strong mode-of-action and efficacy in vitro data, as well as “promising safety and dosing profiles”, will help ESFAM snare a commercial partner. The firm is already in conversations with major animal health businesses. He stated: “I’m currently trying to identify a lead partner. I think our data really speaks for itself. What this therapy has shown in PRRS models is that it completely stops infiltration and viral replication. At ESFAM, we’re not animal health experts. So, we’re not going to take this on any further unfortunately because we’re focused 100% on our antiviral human heath trials. We think the candidates would be better served by a party that is already embedded in the animal health industry.”

Mr Crealy said a potential partner for ESFAM could emerge from China, given the size and value of the country’s pig industry. He pointed out the Chinese pig sector loses about 15-30% of its population due to disease and culling. China is much more primed to take on prevention measures for a host of diseases in the wake of its African swine fever crisis. Companies in Asia are more likely to take on R&D projects at an earlier stage than businesses in the US or Europe, Mr Crealy suggested.

ESFAM was founded in 2015, by a team of academics based in Australia that developed a drug discovery platform for small molecule viral targets. The firm’s pipeline features the PRRS candidates, as well as drugs for COVID-19 and advanced prostate cancer.

Mr Crealy told IHS Markit Animal Health: “PRRS is one of the greatest risks to global food security and is caused by a family of single-stranded, positive RNA viruses Arteriviridae order Nidovirales. PRRS acts in a similar way to HIV/AIDS, rapidly modifying surface proteins and destroying host immune cells. PRRS viruses have evolved to exploit a vulnerability in immune cells (porcine alveolar macrophages), which allow the virus to avoid detection, enter healthy cells and then hijack the cells ‘machinery’ to replicate.

“Destruction of the immune cells and migration of the virus to other tissues leads to immunosuppression, and respiratory disorders in pigs of all ages and severe reproductive failures in pregnant sows. Vaccine treatments, which rely on a healthy immune response, are not consistently effective in prevention of herd infections and no treatments exist for acute infection of highly prevalent strains. There is therefore very strong market demand for our differential and potentially synergistic mode of action to current vaccine therapy.”

ESFAM’s inhibitors act in a similar way to the successful antiviral therapies used to treat HIV/AIDS in humans. They are specifically designed to stop PRRS from exploiting immune cell vulnerability and to deny the virus entry into healthy cells.

Transmission of the virus via respiration is prevented by blocking its ability to replicate in the lung. While the candidates have been developed as an injectable, Mr Crealy noted ESFAM is working on an oral formulation.

He commented: “The PRRS candidates have an exceptional patent landscape, both in terms of chemical entities and processes that are novel, inventive and industrially applicable.”

The development of the porcine candidates was supported by Charles River Laboratories, Kansas State University and Wuxi AppTec – the latter will carry out manufacturing activities in Shanghai. Mr Crealy said manufacturing will be able to scale up to reach a target global market of around 700 million pigs, while the simple and low-cost scale-up process “means these therapies are ideally suited to a new or existing pharmaceutical or animal health manufacturer”. Mr Crealy was brought onboard at ESFAM to foster international partnerships for the PRRS candidates and the company’s other portfolio compounds in human health. His background is in clinical pharmacology, while he has also held Asia Pacific-based business development and M&A roles with major pharmaceutical companies such as Sanofi (where he was exposed to the company’s animal health business Merial) and AstraZeneca.

“In the last seven years, I have been managing a number of private investments that focus on innovative early-stage technologies, including therapies addressing critical human and animal health challenges in Asia,” Mr Crealy remarked. “I bring strong relationships with global pharmaceutical companies, capital funds and emergent human animal health players in Asia, such as Fosun, Qilu, Buchang, Shandong Lukang, New Hope, Ringpu etc. My passion is to help develop early stage innovation technologies, to meet unmet clinical needs in Asia and animal and human health.

“Over the years, I’ve seen this incredible shift happening in the animal health industry. It’s something that has also happened in human pharma. The big global companies have moved away from diversified R&D programs towards more focused partnerships. That has left a bit of gap for regional companies and universities that generate incredible insights into disease states.”