Rapafusyn Pharmaceuticals Secures $28 Million Series A Financing to Advance Its Non-degrader Molecular Glue Drug Discovery Platform

On June 20, 2024, Rapafusyn Pharmaceuticals (hereinafter referred to as “Rapafusyn”), a global leader in the discovery and development of innovative drugs based on non-degrading molecular glues, announced the initial closing of its oversubscribed Series A financing round. The total Series A funding reached $28 million, jointly led by 3E Bioventures and Proxima Capital, with participation from LapamCapital. The proceeds will be used to advance Rapafusyn’s macrocyclic peptide-based non-degrading molecular glue technology platform, propel its innovative drug pipeline targeting a broad range of diseases, and further enhance its internal new drug R&D capabilities.

Rapafusyn boasts an industry-leading RapaGlue™ molecular library, capable of rapidly generating novel candidate drug molecules for targets that have traditionally been difficult to address or are currently considered undruggable by other methods. This innovative breakthrough offers highly promising solutions for numerous undruggable targets, marking a significant advancement in drug discovery and development to meet patients’ urgent medical needs.

“Previous non-degradative molecular glue drugs were discovered by chance, whereas the RapaGlue™ platform has, for the first time, enabled targeted rational design for the systematic discovery of innovative non-degradative molecular glue therapeutics.”Dr. Jun O. Liu, Scientific Founder of Rapafusyn and a Pioneer in the Field of Molecular GluesIn 1991, he, together with Professor Stuart Schreiber and colleagues at Harvard University, pioneered the discovery that FK506 and cyclosporine A exert their pharmacological effects through a molecular glue mechanism, thereby laying the foundation for the field of non-degrading molecular glues.

“Our RapaGlue™ platform holds promise for delivering disruptive new therapies to patients. This innovative class of non-degradable molecular glue compounds combines the advantages of molecular glues and cyclic peptides, enabling the facile generation of novel drug candidates with favorable cell membrane permeability. Our robust platform empowers us to develop pioneering therapeutics targeting disease pathways that are challenging to address with many other compound classes.”Dr. Sean X. Hu, CEO of RapafusynThe comment stated, “We are deeply honored to have such distinguished investors as 3E Bioventures, Proxima Capital, and LapamCapital participate in this financing round.”

“Rapafusyn offers a novel class of macrocyclic molecules with non-degradative molecular glue functionality. It can target cell membrane proteins or intracellular targets, including traditionally undruggable targets such as protein-protein interaction (PPI) targets, transcription factors, solute carriers (SLCs)/transporters, and ion channels.”Dr. Karen Liu, Founding Partner of 3E Bioventures“Rapafusyn is another revolution in the field of small-molecule drugs,” he said. “This platform excites me greatly because it significantly expands the chemical space for small-molecule therapeutics. Traditionally, small-molecule drugs have been constrained by Lipinski’s Rule of Five. Although protein-degrading molecules such as PROTACs, which have gained popularity in recent years, have broken through this limitation, they are restricted to targets that can be degraded.”

Haolin Sung, Partner at Proxima Capitalstated: “We are highly bullish on Rapafusyn’s non-degrading molecular glue platform and are very pleased to invest in it. It possesses clear differentiating advantages, offering many benefits over other drug modalities in addressing challenging or difficult-to-drug disease targets. We are also deeply impressed by the capabilities of Rapafusyn’s world-class operational and advisory teams, and we firmly believe in the company’s success.”

Zhihua Yu, Founding Managing Partner of LapamCapitalstated: “By applying innovative and proven methodologies, Rapafusyn is uniquely positioned to develop global first-in-class drugs targeting challenging or undruggable disease targets, thereby addressing unmet clinical needs. We believe in and look forward to Rapafusyn’s early development of innovative therapies that will benefit patients worldwide.”

3E Bioventures focuses on investing in hard-tech innovations within the global leading life sciences sector. Approximately half of its investment portfolio is allocated to Biotech, specifically innovative pharmaceuticals, including novel drug modalities and drug discovery platforms. The other half is dedicated to TechBio, which encompasses disruptive innovations arising from cross-disciplinary technological convergence, including but not limited to next-generation medical devices, diagnostic tools, and life science research instruments that integrate IT, sensors, data science, and artificial intelligence with biology. Rooted in China and oriented toward the global market, 3E Bioventures aims to advance frontier scientific progress in the life sciences and make positive contributions to human health and well-being.

Proxima Capital is a specialized investment firm focused on innovative medical technologies and disruptive biotechnologies, dedicated to serving exceptional innovative healthcare enterprises with significant growth potential. Managed and operated by a professional team with extensive experience in the medical industry, Proxima Capital boasts diverse and international expertise, professional backgrounds, and industry networks. The firm currently manages multiple RMB and USD funds, covering stages from angel to growth. Proxima Capital has established a leading healthcare entrepreneurship ecosystem, facilitating connections between its portfolio companies and high-quality clinical and industrial resources, achieving remarkable experience and results.

Headquartered in Beijing, LapamCapital is a leading venture capital firm specializing in biomedicine in China. Currently, LapamCapital manages five RMB-denominated funds and one USD-denominated fund, with total assets under management exceeding RMB 10 billion. It is the only biomedical investment institution to date that has received capital commitments from both of China’s top two RMB limited partners: the National Council for Social Security Fund and the National Small and Medium Enterprises Development Fund.LapamCapital focuses on investments in innovative drugs and innovative medical devices, primarily targeting startups and early-to-mid-stage companies. To date, it has invested in over 120 enterprises, including more than 100 innovative drug companies and over 20 innovative medical device companies. Its portfolio features numerous standout projects such as Beta Pharma (SZ.300558), RemeGen (SH.688331), Yihong Pharmaceuticals (SH.688176), Kaiyin Technology (SH.688687), ImmuneOnco (HK.01541), Aier Eye Hospital Group’s subsidiary Aibo Medical (SH.688050), Contineum Pharmaceuticals (GYRE), Huahao Zhongtian, BinHui Bio, and Wuhe Bo’ao.Many partners within LapamCapital’s management team possess over 20 years of R&D and managerial experience in the international and domestic biomedical industries, enabling them to provide comprehensive value-added services to portfolio companies.

Rapafusyn Pharmaceuticals originated from the laboratory of Dr. Jun O. Liu, Professor of Pharmacology and Molecular Sciences at Johns Hopkins University. Co-founded in 2015 by Professor Liu and Dr. Shengjun Yan, Rapafusyn is a next-generation bifunctional macrocyclic drug development platform company dedicated to developing non-degradative molecular glues to address undruggable targets and improve patient therapeutic outcomes. The company has designed and synthesized large DNA-encoded libraries (DELs) and macrocyclic molecular glue libraries (RapaGlues™) capable of binding to FKBP. These compounds inhibit the natural activity of disease-target proteins by forming novel protein-protein interactions (PPIs). Featuring an “FKBP-binding domain” and a target protein-specific “effector domain,” these compounds form high-affinity, highly selective ternary complexes with FKBP and the target protein, thereby modulating the function of disease-related target proteins. RapaGlues™ successfully generate new chemical starting points for previously undruggable targets and exhibit favorable cell permeability from the initial screening stage, significantly enhancing their potential and application prospects in drug development. Their modular architecture facilitates structure-activity relationship (SAR) studies and subsequent optimization of efficacy, selectivity, and physicochemical properties, thereby accelerating drug discovery and development.