Diagonal Taps Finance Veteran to Steer Rare Disease Pipeline Through Pivotal Growth

WATERTOWN, Mass. – May 05, 2026 – Diagonal Therapeutics, a clinical-stage biotechnology company pioneering a new class of antibody drugs, has appointed industry veteran Jonathan Piazza as its Chief Financial Officer. The move signals a strategic reinforcement of its leadership as the company prepares to advance its lead candidate into human trials and navigate the high-stakes world of rare disease drug development.

Piazza joins Diagonal with over 25 years of experience, bringing a formidable track record in corporate finance, capital markets, and M&A. His appointment comes at a critical juncture for the Watertown-based firm, which has amassed $255 million in funding to develop its unique "clustering antibody" platform aimed at correcting the root causes of severe genetic disorders.

A Strategic Play for Clinical and Financial Growth

In the competitive and capital-intensive biotech sector, the transition from preclinical research to clinical development is a moment of immense opportunity and risk. Diagonal's decision to bring in a CFO with Piazza's background underscores a clear strategy to expertly manage this pivotal phase. His past successes include guiding Orbital Therapeutics to its acquisition by Bristol Myers Squibb and leading Silverback Therapeutics through a successful initial public offering (IPO) and a subsequent merger.

This experience is precisely what emerging biotechs seek to de-risk their path to market. “Jonathan brings extensive leadership experience and a demonstrated track record of supporting portfolio development through strategic capital formation in high-growth biotechnology companies,” said Alex Lugovskoy, Ph.D., Founder and Chief Executive Officer of Diagonal. “His expertise in guiding organizations through value-generating inflection points will be instrumental as we advance DIAG723 through clinical development and progress our early-stage pipeline.”

Diagonal is well-capitalized to pursue these goals, having launched in 2024 with a $128 million Series A and recently securing an oversubscribed $125 million Series B in January 2026. The impressive funding rounds were supported by a syndicate of top-tier investors, including Atlas Venture, BVF Partners, Sanofi Ventures, and RA Capital Management, signaling strong confidence in the company’s science and strategy. Piazza’s role will be to steward this capital effectively while charting a financial course toward future milestones, which could include further private or public financing, strategic partnerships, or M&A activity.

“Diagonal is entering a pivotal chapter as it advances DIAG723 and additional programs into the clinic,” Mr. Piazza stated. “I look forward to partnering with the team to help realize that goal.”

Advancing a New Frontier in Rare Disease Treatment

At the heart of Diagonal's strategy is its proprietary DIAGONAL Product Engine, a platform designed to discover and optimize "clustering antibodies." Unlike traditional antibodies that typically block a biological target, Diagonal's therapies are designed to bring two or more cell-surface receptors together. This clustering action can reactivate or modulate signaling pathways that have been disrupted by genetic mutations, offering a way to repair cellular function rather than merely managing symptoms.

The company's lead asset, DIAG723, exemplifies this innovative approach. It targets two debilitating and rare conditions: hereditary hemorrhagic telangiectasia (HHT) and pulmonary arterial hypertension (PAH). In both diseases, dysregulated signaling of the ALK1 pathway in endothelial cells leads to devastating vascular abnormalities. DIAG723 is designed to restore this lost signaling.

For patients with HHT—a disorder affecting up to 330,000 people in the U.S. and Europe—there are currently no approved drug treatments. The condition causes fragile arteriovenous malformations that can lead to severe, chronic bleeding and life-threatening complications. In preclinical studies, DIAG723 has shown the ability to not only prevent but also reverse these malformations and the associated anemia. In recognition of its potential, the therapy has received Orphan Drug Designation from both the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) for HHT, a status that provides significant development incentives and years of market exclusivity upon approval.

Navigating a Competitive Therapeutic Landscape

While the opportunity in HHT is characterized by a high unmet need, the landscape for PAH is more established, yet rapidly evolving. The PAH market features a dozen approved therapies, but most focus on vasodilation to alleviate symptoms. A major shift occurred recently with the FDA approval of Merck’s sotatercept (Winrevair), the first therapy designed to modify the course of the disease by rebalancing cell signaling.

This market shift plays directly into Diagonal's strategy. DIAG723, with its aim of restoring ALK1 signaling, is positioned to be part of this new wave of disease-modifying agents for PAH. Preclinical models have shown its potential to prevent disease development and cardiac remodeling. By targeting the underlying biology, Diagonal hopes to offer a more profound and lasting benefit than existing symptomatic treatments. Piazza's financial acumen will be critical in positioning DIAG723 within these distinct competitive environments, allocating resources for clinical trials designed to demonstrate clear differentiation and value to regulators, physicians, and payers.

The Leadership Imperative in Modern Biotech

Piazza's appointment also reflects a broader industry trend: the increasing premium placed on seasoned leadership to navigate the complexities of modern drug development. His career path is a testament to the diverse expertise required. After starting in engineering and marketing at Abbott Laboratories, he transitioned to finance, eventually spending 15 years in healthcare investment banking at powerhouse firms like Goldman Sachs and Barclays before taking on CFO roles at innovative biotechs.

This blend of scientific understanding, financial market savvy, and operational experience is becoming a prerequisite for C-suite executives in a sector where scientific breakthroughs must be paired with flawless execution and strategic capital management. The backing from sophisticated investors like Sanofi Ventures, whose partner Dr. Paulina Hill recently joined Diagonal's board, further validates that the company is building a team capable of translating its promising science into tangible therapies.

As Diagonal Therapeutics prepares to enter the clinic, the addition of Jonathan Piazza fortifies its foundation. With a powerful technology platform, a well-funded pipeline, and now a deeply experienced financial strategist at the helm, the company is poised to make a meaningful impact on the treatment of rare diseases where patients have long awaited a breakthrough.