– Proceeds to support development of ProfoundBio's differentiated clinical-stage ADC pipeline, including the planned pivotal trial of rinatabart sesutecan (Rina-S)

– Financing led by Ally Bridge Group, bolstered by contributions from world-class healthcare dedicated and mutual fund institutional investors, including Nextech Invest, T. Rowe Price, Janus Henderson Investors, RA Capital Management, and OrbiMed, among others

– Andrew Lam, Eric Dobmeier and Enoch Kariuki to join ProfoundBio Board of Directors 

-- ProfoundBio, a clinical-stage biotechnology company developing novel antibody-drug conjugate (ADC) therapeutics for patients with cancer, today announced an oversubscribed $112 million Series B financing supported by a syndicate of top healthcare dedicated and mutual fund institutional investors. This financing underscores the new and existing investor confidence in ProfoundBio's innovative approach to cancer treatment and is expected to accelerate the development of its comprehensive ADC portfolio, including the planned pivotal trial of rinatabart sesutecan (Rina-S) for the treatment of ovarian cancer.

The funding round was led by Ally Bridge Group, with substantial contributions from new investors including Nextech Invest, funds and accounts advised by T. Rowe Price Associates, Inc., Janus Henderson Investors, RA Capital Management, OrbiMed, Surveyor Capital (a Citadel company), Medicxi, Logos Capital, Octagon Capital, Piper Heartland Healthcare Capital and LifeSci Venture Partners, as well as continued support from existing investors Lilly Asia Ventures (LAV) and LYFE Capital.

"We are excited to welcome this premier group of life science investors. Their commitment is a testament to our progress and our mission to develop innovative ADCs with the potential for improved clinical outcomes for patients," said Erin Lavelle, Chief Operating Officer and Chief Financial Officer of ProfoundBio. "This investment boosts our momentum, especially with three clinical-stage candidates in our portfolio and another poised for clinical trials in the next few months. It's a pivotal step in enabling significant milestones and delivering key data readouts this year and through 2025. The addition of Andrew Lam, Eric Dobmeier, and Enoch Kariuki to our board brings invaluable expertise, strengthening our path to redefine patient care."

Commitment to Innovative Cancer Therapy

The capital raised will support ProfoundBio's diverse array of clinical and preclinical ADC programs, primarily targeting solid tumor cancers. Key programs include:

• Rina-S, a folate receptor-alpha (FRα) targeted ADC, in Phase 2 trials for ovarian and endometrial cancers, with pivotal studies in ovarian cancer planned for later this year.

• PRO1160, a CD70 targeted ADC, in Phase 1 trials with initial results expected in 2024.

• PRO1107, a protein tyrosine kinase 7 (PTK7) targeted ADC, in Phase 1 trials with initial results anticipated in 2025.

• PRO1286, a bi-specific ADC, anticipated to enter the clinic in 2024.

Baiteng Zhao, Ph.D., Chairman of the Board and Chief Executive Officer of ProfoundBio stated, "This Series B financing is an important milestone in our mission to redefine cancer treatment. Our ADC pipeline programs, led by Rina-S, demonstrate our dedication to bringing groundbreaking therapies to patients with cancer. With this support, we are better positioned to advance our clinical trials and offer new differentiated approaches. We welcome our new board members and look forward to this next chapter of ProfoundBio."

New Board of Directors Appointments

ProfoundBio strengthens its board of directors with the addition of Andrew Lam from Ally Bridge Group, alongside two independent directors, Eric Dobmeier and Enoch Kariuki, who bring a breadth of experience in biotechnology and investment.

• Andrew Lam, Pharm.D., Managing Director and Head of Biotech Private Equity at Ally Bridge Group, is known for his strategic and capital markets insights based on his extensive expertise in the life sciences sector.

• Eric Dobmeier brings over two decades of leadership, operating and business development experience in biotechnology companies, having led significant growth initiatives at Seagen and Chinook Therapeutics.

• Enoch Kariuki, Pharm.D., brings extensive background in healthcare strategy, investment banking, and venture capital, contributing valuable financial and strategic acumen.

Joining existing board members Baiteng Zhao, Ph.D. (co-founder), Lynn Yang (HongShan), and Josh Jin (LAV), these new members bring considerable experience and expertise to ProfoundBio. 

"ProfoundBio is led by an experienced management team with a proven track record of global approvals of ADC therapeutics and decades of research and development experience focused on this modality," said Dr. Lam. "We are proud to be supporting a great team that has advanced an exciting pipeline of differentiated and potentially best-in-class and first-in-class ADCs."                  

ProfoundBio's Cutting-Edge Investigational ADC Programs

Rinatabart sesutecan (Rina-S, PRO1184) is a FRα-targeted ADC being developed as a novel treatment option for patients with ovarian and endometrial cancer, and potentially other FRα-expressing cancers. Rina-S is comprised of a FRα-directed antibody conjugated to sesutecan, ProfoundBio's novel, proprietary hydrophilic exatecan-based linker-drug, at a homogeneous drug-to-antibody ratio (DAR) of 8. Exatecan is a highly potent, membrane permeable topoisomerase-1 inhibitor with strong bystander effect. The linker component of sesutecan is a highly hydrophilic, stable, cleavable linker designed to mask the hydrophobicity of exatecan, enabling high DAR and efficient delivery of the exatecan payload to tumors while maintaining favorable physicochemical and pharmacokinetic properties of the ADC. Rina-S is currently being evaluated in a Phase 1/2 clinical trial (NCT05579366) and has been granted Fast Track Designation by the U.S. Food and Drug Administration (FDA) for the treatment of patients with FRα-expressing high-grade serous or endometrioid platinum-resistant ovarian cancer.

PRO1160 is an ADC consisting of a CD70-targeted antibody conjugated to ProfoundBio's novel, proprietary hydrophilic exatecan-based linker-drug, sesutecan.  CD70 is a protein expressed on both solid tumors and hematological malignancies including renal cell carcinoma, nasopharyngeal carcinoma, and non-Hodgkin lymphoma, yet is largely absent in normal tissues. With preclinical results showcasing encouraging pharmacokinetics, efficacy, and tolerability, PRO1160 is emerging as a potential advancement in the treatment of these cancers and is currently being evaluated in a Phase 1/2 clinical trial (NCT05721222).

PRO1107 is an ADC consisting of a PTK7-targeted antibody conjugated to ProfoundBio's novel, proprietary hydrophilic MMAE-based linker-drug, LD343, at a homogeneous DAR of 8. MMAE is a potent, membrane-permeable microtubule inhibitor that has been clinically validated as an ADC payload by multiple marketed ADCs incorporating MMAE in the linker-drug vedotin at a DAR of 4. The linker component of LD343 is a highly hydrophilic stable, cleavable linker designed to mask the hydrophobicity of MMAE, enabling high DAR and efficient delivery of the MMAE payload to tumors while maintaining favorable physicochemical and pharmacokinetic properties of the ADC.  PRO1107 is currently being evaluated in a Phase 1/2 clinical trial (NCT06171789).

PRO1286 is a bispecific ADC that has the potential to treat multiple tumor types. PRO1286 is built on the clinically validated sesutecan platform and is anticipated to begin clinical trials in 2024.

About ProfoundBio

ProfoundBio is a clinical-stage biotechnology company focused on the development of novel antibody-based therapeutics for patients with cancer. Built on internally developed, innovative, and proprietary technology platforms, ProfoundBio has developed a pipeline consisting of multiple ADC drug candidates targeting solid tumors and hematological malignancies. The company's disclosed development pipeline consists of rinatabart sesutecan (Rina-S; PRO1184), an ADC targeting FRα; PRO1160, an ADC targeting CD70; PRO1107, an ADC targeting PTK7; and PRO1286, a bispecific ADC targeting two clinically validated, broadly expressed solid tumor antigens. ProfoundBio is headquartered in Seattle, Washington.

For more information, please visit www.profoundbio.com and follow us on LinkedIn.

Investor Contact:
ir@profoundbio.com