BioTheryX, a clinical stage biotechnology company harnessing the power of protein modulation to treat difficult diseases, today announced it has closed a $35 million Series D financing. The round was led by MSD Partners, L.P.

"We are pleased to have closed this financing that will enable us to accelerate expansion of our ongoing clinical trial of BTX-A51, which I believe may ultimately become one of the most significant innovations in the past 40 years for AML patients and their families," said David Stirling, Ph.D., Chairman and CEO of BioTheryX. "Additionally, and equally as important, this funding will support our ongoing work in protein modulation and degradation utilizing proprietary Protein Homeostatic Modulators (PHMs™) and PHM®-based PROTACs, where I believe we have a superior probability of success driven by the large diversity of our molecular binders that afford us advanced structural control in drug design."

In addition to general corporate development purposes, proceeds from the financing will be used to accelerate the timeline of the BTX-A51 Phase 1 clinical trial through the addition of clinical sites beyond Memorial Sloan-Kettering Cancer Center, continue IND-enabling studies for therapeutic candidates utilizing both PHMs™ and PHM®-based PROTACs (proteolysis targeting chimeras), and support more rapid development of the Company's pre-clinical pipeline.

Louis J. DeGennaro, Ph.D., President and CEO, The Leukemia & Lymphoma Society (LLS), and BioTheryX Board Member, stated, "LLS has been pioneering breakthrough blood cancer research since 1949, and through innovative initiatives like our Therapy Acceleration Program® (TAP) we're doing more than any cancer nonprofit to advance cutting-edge research and cures. As the first equity investment made through TAP, I am pleased to see BioTheryX's continued progress on promising approaches to treat blood cancers that may make meaningful differences in patients' lives."

In conjunction with the financing, Robert Platek, a Partner and Portfolio Manager at MSD Partners L.P., will be joining BioTheryX's Board of Directors.

Raymond James' Alex Brown division served as the sole placement agent for the financing.

About BioTheryX

BioTheryX is a clinical-stage biopharmaceutical company focused on restoring protein homeostasis, including protein degradation and modulation, and multi-kinase inhibition to develop treatments intended to extend and improve the quality-of-life of patients with life-threatening diseases. Our principal technology platform centers on targeted protein degradation, as well as PHM® 'molecular glues' that enable the design of small molecules to regulate protein equilibrium. This technology is designed to utilize the body's own protein disposal system to selectively degrade and remove disease-causing proteins. It has potential applicability to a broad range of diseases, including targets that have to date been considered 'undruggable'. For more information, please visit www.biotheryx.com.

About MSD Partners, L.P.

MSD Partners, L.P. is an SEC-registered investment adviser that was formed in 2009 by the principals of MSD Capital, L.P. to enable a select group of investors to invest in strategies that were developed by MSD Capital (the private investment firm for Michael Dell and his family). MSD Partners utilizes a multi-disciplinary investment strategy focused on maximizing long-term capital appreciation by making investments across the globe in the equities of public and private companies, credit, real estate and other asset classes and securities. MSD Partners is headquartered in New York with an additional office in Santa Monica. Additional information regarding MSD Partners may be found at msdpartners.com.