Protego Biopharma Advances Novel AL Amyloidosis Treatment with $130M Series B Funding

Protego Biopharma, a San Diego-based biotechnology company, has successfully raised $130 million in a Series B funding round to advance its innovative approach to treating amyloid light-chain (AL) amyloidosis. The funding, led by Novartis Venture Fund and Forbion, will propel the company's lead candidate, PROT-001, into late-stage clinical testing, potentially offering a paradigm shift in the treatment of protein misfolding disorders.

A New Approach to AL Amyloidosis

AL amyloidosis is a rare and potentially fatal condition caused by abnormal plasma cells producing excess light chain proteins that misfold and form fibrils, depositing in various organs and tissues. Unlike current treatments that focus on symptom management or plasma cell elimination, Protego's PROT-001 aims to stabilize immunoglobulin light chains, preventing amyloid buildup and directly addressing the disease's root cause.

Brent Warner, CEO of Protego Biopharma, emphasized the potential impact of their approach: "There is very clear data that toxic light chain is really what's driving a lot of the mortality in this disease. We believe our approach may represent a step forward compared to current therapies."

Clinical Development and Future Plans

Protego has already initiated an early-stage study of PROT-001, with results expected next year. The substantial Series B funding will support the launch of a Phase 2/3 trial, scheduled to begin in the second half of 2026. This ambitious timeline reflects the company's confidence in its technology and the urgent need for more effective treatments in AL amyloidosis.

The company's strategy is rooted in human genetics and a unique pharmacological chaperone mechanism. Warner stated, "In a disease like this, you may not necessarily need a sledgehammer, you just may need a sharper knife to cut it."

Industry Context and Competitive Landscape

Protego's progress comes at a critical time for the AL amyloidosis field, following recent setbacks experienced by other pharmaceutical companies. In May 2025, Prothena shelved its therapy after disappointing study results, while AstraZeneca's acquired drug failed in a late-stage study in July of the same year.

These industry challenges have only strengthened Protego's resolve. Warner noted, "Those failures give us a lot of conviction on our approach." The company believes that by intervening earlier in the disease process and preventing amyloid accumulation, they may achieve better outcomes than previous attempts focused on clearing existing deposits.

Dr. Tim Lohoff, principal at Forbion, one of the lead investors, commented on their support for Protego: "At Forbion, we invest in bold teams turning breakthrough science into tangible medical and commercial impact, and Protego exemplifies that vision."