New Investment in Prometheus Biosciences

LEI: 549300Q7EXQQH6KF7Z84

09 November 2020

RTW Venture Fund Limited

New Investment in Prometheus Biosciences

RTW Co-Leads $130 Million Financing Round in Prometheus Biosciences

RTW Venture Fund Limited (the "Company"), the London Stock Exchange-listed investment company focused on identifying transformative assets with high growth potential across the life sciences sector, is pleased to note the announcement by Prometheus Biosciences, Inc. ("Prometheus") on 09 November 2020 of its completion of a $130 million financing round co-led by RTW Investments, LP (the "Investment Manager").

The Company, alongside other investment vehicles of the Investment Manager, confirms that it participated in the financing round together with other investment firms.

Prometheus is a US-based privately held biotechnology company pioneering a precision medicine approach to the discovery, development, and commercialization of novel therapeutic and companion diagnostic products for the diagnosis and treatment of inflammatory bowel disease (IBD). Prometheus plans to use the proceeds from the financing round to advance its lead antibody program targeting TL1A into clinical development for IBD and expand its precision medicine Prometheus 360 platform to further identify therapeutic targets in this indication.

The Company's investment in Prometheus is its eleventh portfolio company addition following its IPO in October 2019. The Investment Manager is looking forward to growing the Company's investment pipeline and updating shareholders on further opportunities in due course.

Roderick Wong, MD, Managing Partner and Chief Investment Officer of the Investment Manager, said:

"We are excited to co-lead this financing round and support Prometheus' pioneering approach to develop a best-in-class treatment for IBD, as well as continue to expand its precision medicine platform to improve outcomes for IBD patients. For RTW Venture Fund, the addition of Prometheus further diversifies its portfolio across innovative therapeutic modalities and disease areas."

Prometheus' announcement can be accessed on its website at: www.prometheusbiosciences.com, the full text of which is contained below.

For Further Information

RTW Investments, LP +1 (646) 343 9280Stephanie Sirota, Chief Business OfficerAlexandra Taracanova, PhD, Director of Investor Relations

Julia Enright, Business Development Associate

Buchanan +44 (0)20 7466 5107Charles Ryland

Henry Wilson

About RTW Venture Fund Limited:

RTW Venture Fund Limited (LSE: RTW) is an investment fund focused on identifying transformative assets with high growth potential across the biopharmaceutical and medical technology sectors. Driven by a long-term approach to support innovative businesses, RTW Venture Fund invests in companies developing next-generation therapies and technologies that can significantly improve patients' lives.

RTW Venture Fund Limited is managed by RTW Investments, LP, a leading healthcare investment firm with deep scientific expertise and a strong track record of supporting companies developing life-changing therapies.

Visit the RTW website at www.rtwfunds.com for more information.

Prometheus Biosciences Announces $130 Million Financing to Advance Precision Medicines for the Treatment of Inflammatory Bowel Disease

- New investors include Eventide, RTW, Perceptive Advisors, Cormorant Capital, Cowen Healthcare Investments, Point72 and Irving Investors -

-Proceeds to accelerate clinical development of PRA023, a potential best in class TL1A antibody for IBD, and expansion of Prometheus' 360 platform -

SAN DIEGO, November 9, 2020 /PRNewswire/ -- Prometheus Biosciences, Inc., ("Prometheus") a biotechnology company pioneering a precision medicine approach to the discovery, development, and commercialization of novel therapeutic and companion diagnostic products for the diagnosis and treatment of inflammatory bowel disease (IBD), today announced the completion of a $130 million equity financing led by Eventide Asset Management and RTW Investments, LP. Additional new investors include Perceptive Advisors, Cormorant Capital, Cowen Healthcare Investments, Point72 Asset management and Irving Investors, with participation from existing investors Ascend Global Investment Fund, Cedars-Sinai Medical Center and Nestlé SA. In connection with the financing, Joy Ghosh, Ph.D. of Eventide Asset Management and Adam Stone of Perceptive Advisors will be joining the Prometheus Board of Directors.

"We are pleased to have the support of such outstanding investors who share our dedication and vision to build the world's leading precision medicine company for IBD," said Mark McKenna, President and CEO of Prometheus. "We are now well-positioned to advance the clinical development of our lead antibody program targeting TL1A associated IBD and grow our emerging pipeline of precision medicine programs designed to deliver life-changing outcomes for patients."

"The IBD treatment landscape has seen limited innovation to date despite an enormous effort to unlock benefit from traditional therapeutic approaches. Prometheus has the potential to disrupt the space with its precision medicine approach as well as its genotype-phenotype Prometheus 360 drug discovery platform designed to create novel IBD medicines to benefit patients," said Joy Ghosh, Ph.D. of Eventide Asset Management.

About Prometheus Biosciences, Inc.

Prometheus Biosciences, Inc. is a privately held biotechnology company pioneering a precision medicine approach to the discovery, development, and commercialization of novel therapeutic and companion diagnostic products for the treatment and diagnosis of IBD. The company's precision medicine platform, Prometheus 360, combines proprietary bioinformatics discovery methods with one of the world's largest gastrointestinal bioinformatics databases to identify novel therapeutic targets and develop therapeutic candidates to engage those targets. Leveraging its expertise in the field including Dr. Tachi Yamada and prominent clinical trialists including Dr. William Sandborn and Dr. Brian Feagan, Prometheus has formed key partnerships to develop targeted therapies for IBD.

Prometheus maintains its headquarters in San Diego, CA. For more information about Prometheus, please visit www.prometheusbiosciences.com.

Contacts:

Investor Relations and Media Contact

Juniper Point

Amy Conrad, (858) 914-1962

IR@prometheusbiosciences.com