Surrozen (NASDAQ:SRZN) Chief Executive Officer Craig Parker used a discussion at a 2026 investor summit to outline the company’s focus on Wnt pathway biology and antibody engineering, with an emphasis on retinal vascular diseases. Parker said Surrozen has worked on Wnt signaling since its founding in 2016 and is now advancing agonistic antibodies designed to activate a receptor called Frizzled-4 (Fzd4), which he described as critical in both embryonic eye development and maintenance of normal retinal and choroidal vessel function.
Wnt pathway rationale in retinal disease
Parker framed the approach as restoring normal vessel architecture and function rather than simply inhibiting disease drivers. He pointed to rare genetic disorders—Norrie Disease and familial exudative vitreoretinopathy (FEVR)—as validation that the Fzd4-mediated pathway must function normally for healthy retinal vessels. While Surrozen is not pursuing those rare indications, Parker said they support the biological rationale for targeting larger markets such as diabetic macular edema (DME), wet age-related macular degeneration (wet AMD), and potentially retinal vein occlusion.
Measuring “disease-modifying” effects
Asked how Surrozen would demonstrate disease-modifying effects in humans, Parker pointed to standard retinal imaging readouts used across the field, including optical coherence tomography (OCT), OCT angiography (OCTA), and wide-field angiography. He also highlighted “areas of retinal non-perfusion” in DME—typically peripheral regions where he said VEGF inhibitors do not revascularize tissue—as a potential differentiating endpoint. Parker said Surrozen has seen revascularization in mouse models and plans to look for that signal in initial clinical trials, alongside reductions in vessel leakage.
He noted that key outcomes in DME trials, including reductions in macular fluid and improvements in visual acuity, can appear quickly—within typical visit intervals of four to 12 weeks—consistent with what has been observed for both anti-VEGF agents and Merck’s Wnt-pathway molecule.
Competitive landscape and Merck readouts
Parker described the current DME and wet AMD market as largely dominated by two products: Roche’s Vabysmo (VEGF/Ang2) and Regeneron’s Eylea (including 2 mg and HD formulations). He said other agents, such as compounded Avastin and Lucentis, represent smaller portions of the market.
Within Wnt biology, Parker said the field has historically had few players pursuing multispecific antibodies, naming Surrozen and work originating from University of Toronto that later became Restoret and Merck’s MK-3000. Parker said Merck acquired an Fzd4/LRP5 molecule from EyeBio, while a broader portfolio of related binders was sold to Roche. He added that Roche may have a “Frizzled LRP” program that could compete with Merck’s and with Surrozen’s partnered program.
On Merck’s ongoing development, Parker said the company has two parallel Phase III trials with the same design, with the first expected to read out in September and the second in March. He said the study compares Restoret alone to monthly ranibizumab (Lucentis), with best-corrected visual acuity (BCVA) at 12 months as the primary endpoint and central subfield thickness (CST) among likely disclosed measures. Parker said results showing meaningful activity, along with “very good safety,” would support Surrozen’s strategy, even if Restoret does not match ranibizumab. He also emphasized that, in his view, differentiation is increasingly driven by retinal anatomy and “drying” endpoints rather than surpassing best-in-class visual acuity gains.
Surrozen’s pipeline: SZN-8141 and SZN-8143
Parker said Surrozen plans a 2026 IND filing for its lead wholly owned program and expects to provide more specificity on timing, trial design, and data expectations “sometime soon.” He described the lead molecule, SZN-8141, as combining Wnt activation with VEGF inhibition. Parker said the Wnt “business end” is pharmacologically similar to the BI and Merck molecules, but Surrozen believes potency and other biophysical characteristics could differentiate it; he called Surrozen’s molecule “the most potent Wnt agonist.”
For the VEGF component, Parker said SZN-8141’s VEGF inhibition behaves “exactly the same as Eylea,” adding that it uses the same publicly available sequences. He said the company is completing late-stage IND-enabling work on chemistry, manufacturing and controls (CMC) and toxicology, and that progress is going well. Parker also said the 220 kilodalton molecule has been “extremely easy to manufacture and to concentrate,” and that Surrozen and Lonza have reached concentrations above 100 mg/mL with low viscosity suitable for intravitreal injection. He said no additional formulation work is required.
Parker said a second program, SZN-8143, is “months behind” SZN-8141 and adds IL-6 inhibition on top of Wnt activation and VEGF inhibition. He cited field data suggesting IL-6 relevance not only in uveitic macular edema (UME) but also in DME, referencing Roche data involving separate injections of anti-VEGF plus anti-IL-6 showing incremental benefit. Parker suggested SZN-8141 may be positioned for DME and wet AMD, while SZN-8143 could be complementary for inflammatory-driven macular edemas such as UME, including what Kodiak calls MEIE.
Partnerships, IP, and financing
Parker discussed Surrozen’s partnership with Boehringer Ingelheim around SZN-413. He said the deal was signed in 2022 and has provided $22.5 million in total proceeds to date, which he characterized as attractive for a preclinical asset. He said the companies had a collaborative research phase, but after Boehringer nominated the program as a development candidate, Surrozen now receives infrequent updates. Parker said he hopes the program enters the clinic soon, but that Surrozen will not know until it appears on clinical trial registries or until the company receives a milestone payment tied to dosing a patient.
On intellectual property, Parker said Surrozen’s scientists are inventors on the patents and that the company has built a broad estate, including about 38 patent applications, some of which have issued. He highlighted what he described as a broad patent covering multivalent Frizzled and LRP5 or LRP6 binding antibodies, and said the company will continue to strengthen its IP around Wnt-activating molecules.
Regarding capital, Parker said Surrozen completed a PIPE financing in March 2025 totaling $175 million, with $75 million received in March and $100 million to be received when its IND is open. He said there are warrants associated with the financing. Parker added that, as of the end of the third quarter (prior to filing the company’s annual report), Surrozen had $80 million in cash.
About Surrozen (NASDAQ:SRZN)
Surrozen, Inc is a clinical-stage biopharmaceutical company focused on developing novel therapeutic antibodies that target the Wnt signaling pathway for applications in tissue repair, regeneration and oncology. Founded in 2012 and headquartered in South San Francisco, California, the company leverages its proprietary SurroBody platform to design bispecific antibody molecules capable of modulating Wnt receptor activity with enhanced tissue specificity.
The SurroBody platform enables the generation of high-affinity, dual-binding antibodies engineered to either activate or inhibit Wnt signaling, a pathway critical to cell proliferation, differentiation and homeostasis.
