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4BIO Capital Portfolio Company Ray Therapeutics Closes Oversubscribed $100M Series A Financing

- Ray Therapeutics Closes Oversubscribed $100M Series A Financing

- Series A follows initial seed investment from 4BIO Capital in 2021

- Funds will advance Ray Therapeutics’ pipeline of optogenetics gene therapy programs for blinding retinal diseases


London & San Francisco, CA, 16 May 2023 – 4BIO Capital (“4BIO” or “the Group”), an international venture capital firm unlocking the treatments of the future by investing in advanced therapies and other emerging technologies, today announces that its portfolio company, Ray Therapeutics, a leading optogenetics company, has raised an upsized and oversubscribed $100M Series A financing.


The round follows initial seed investment from 4BIO Capital as well as the founders and well-known biotech entrepreneurs and was led by Novo Holdings A/S, and joined by 4BIO Capital, Deerfield Management, Norwest Venture Partners, Platanus, MRL Ventures Fund, the therapeutics-focused corporate venture fund of Merck & Co., Inc. The funding will advance multiple programs targeting blinding diseases of the eye through clinical development.


“We have been convinced of the significant potential of Ray Therapeutics’ groundbreaking optogenetic approach right from the start, and in the short period of time following our seed investment in 2021, they have made remarkable progress,” said Dima Kuzmin, Managing Partner at 4BIO Capital. “With the team’s proven track record in developing regenerative medicines for ophthalmology indications and the mutation-independent nature of their approach, these novel gene therapies have the potential to reach more patients with a one-time intravitreal injection that could last a lifetime. We are happy to continue supporting the company through this financing round and beyond and look forward to their continued success and the transformative impact that this technology will have on patients’ lives.”


“This Series A financing marks a significant milestone in our mission to address the urgent unmet medical need of patients with blinding diseases,” said Paul Bresge, CEO & Co-Founder, Ray Therapeutics. “We are incredibly grateful for the support of 4BIO Capital, our other early investors and the California Institute for Regenerative Medicine (CIRM) who have been instrumental in our growth. We are excited by this new funding, led by Novo Holdings, with a top-tier investor syndicate which will accelerate our pipeline of potential first-in-class optogenetic gene therapies for patients.”


Visual optogenetics is a therapeutic modality that uses gene therapy to deliver a light sensitive protein to cells in the retina. Light entering the eye can then stimulate these cells to produce a visual signal that is sent to the brain. Ray Therapeutics has developed an optogenetic platform to bioengineer a next generation pipeline of genotype independent therapeutics for vision restoration in multiple retinal diseases where the normal light sensing cells (photoreceptors) are lost, for example retinitis pigmentosa, other inherited retinal dystrophies and macular degeneration. The company’s lead candidate, RTx-015, is expected to begin first-in-human clinical trials shortly.


“Ray Therapeutics’ optogenetic gene therapies have the potential to address a significant unmet need by using light-sensitive proteins to restore visual function in damaged retinal cells,” said Jeffrey Heier, M.D., the Director of the Vitreoretinal Service and Director of Retina Research at Ophthalmic Consultants of Boston. “RTx-015 has shown impressive results in preclinical studies and offers hope to patients who currently have limited to no treatment options with retinitis pigmentosa and other inherited retinal degenerations. These novel therapies could significantly improve the lives of individuals with blinding disorders, by potentially restoring vision with the power of optogenetics.”


In connection with the financing, Ray Camahort, Ph.D., Partner at Venture Investments at Novo Holdings, Tiba Aynechi, Ph.D. General Partner, Norwest Venture Partners and Hannah Chang, M.D., Ph.D., Managing Director, Platanus, will join the Board of Directors at Ray Therapeutics. Brian Chow Ph.D., Principal at Deerfield and Jason Ruth Ph.D., Partner, MRL Ventures Fund, will join as Board Observers. Dr Dima Kuzmin will continue representing 4BIO Capital on the Board.

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