FZD4

Announces strategic prioritization of clinical programs to focus on development of SZN-043 for Alcohol-Associated Hepatitis SZN-043- Completed enrollment for the Phase 1a clinical trial in chronic liver disease patients and healthy volunteers- Expect to announce Phase 1a safety and pharmacodynamic data in Q1 2024- Expect to initiate enrollment in the Phase 1b clinical trial in patients with alcohol-associated hepatitis in 2024 and anticipate proof-of-concept data may be available in the second half of 2024 SZN-1326- Company discontinues clinical development of SZN-1326 in inflammatory bowel disease due to the challenges of identifying a safe and effective dose for further development and other strategic considerations $43.4 million in cash, cash equivalents, and marketable securities as of September 30, 2023 resulting in cash runway into 2025 SOUTH SAN FRANCISCO, Calif., Jan. 18, 2024 (GLOBE NEWSWIRE) -- Surrozen, Inc. (“Surrozen” or the “Company”) (Nasdaq: SRZN), a company pioneering targeted therapeutics that selectively activate the Wnt Pathway for tissue repair and regeneration, today announced that enrollment for the SZN-043 Phase 1a clinical trial in patients with chronic liver disease and healthy volunteers is complete. The Company expects to release safety and pharmacodynamic data in Q1 2024. In addition, Surrozen anticipates initiating enrollment in the Phase 1b portion of the study in patients with alcohol-associated hepatitis soon with proof-of-concept data from the study potentially available in the second half of 2024. Following the completion of the Phase 1 single ascending dose clinical trial for SZN-1326, the Company will discontinue development of SZN-1326 in inflammatory bowel disease (IBD). The decision was based on the challenges of identifying a safe and potentially effective dose along with strategic considerations including the significant clinical development expenses and market competition in IBD. SZN-1326 has been evaluated in a Phase 1 single ascending dose clinical trial in 37 healthy volunteers in doses ranging from 0.01mg to 25mg. Several subjects at higher dose levels experienced asymptomatic liver transaminase elevations, including four subjects with grade 3 ALT and AST elevations. The Company previously reported that 3 of these 4 subjects had grade 3 ALT and AST elevations in 2022. No other clinically significant laboratory abnormalities were observed, and the transaminase elevations resolved spontaneously in all subjects. No serious adverse events were observed during the study. While no safety signal was observed at lower doses, lower dose levels would not be expected to activate Wnt signaling and produce a pharmacologic effect in the intestine. "Although the decision to discontinue the SZN-1326 inflammatory bowel disease development program is disappointing, we want to thank the subjects, our collaborators and the medical professionals who participated and helped advance our understanding of Wnt mimetics,” said Craig Parker, President and Chief Executive Officer of Surrozen. “One of the compelling aspects of Wnt biology and our technologies is the potential to apply them across a range of potential tissues and diseases. Importantly, SZN-043 represents a different antibody technology and approach to modulating Wnt signaling compared to SZN-1326. Given the potential challenges in IBD and attractive opportunities in other areas, we are excited to continue to progress SZN-043 for alcohol-associated hepatitis, advance our pipeline of research stage programs and support our collaboration with Boehringer Ingelheim to advance SZN-413 into development." About SZN-043 for Alcohol-Associated Hepatitis SZN-043 is the first development candidate using Surrozen’s SWEETS™ technology. Surrozen is developing SZN-043 for severe liver diseases, initially focusing on alcohol-associated hepatitis. The Company expects to announce safety and pharmacodynamic data from SZN-043 Phase 1a clinical trial in patients with chronic liver disease and in healthy volunteers in Q1 2024. The company anticipates enrolling patients with alcohol-associated hepatitis in a Phase 1b clinical trial in 2024 and expects that proof-of-concept data from this trial may be available in the second half of 2024. About SZN-413 for Retinal Diseases SZN-413 is a bi-specific antibody targeting Fzd4-mediated Wnt signaling designed using Surrozen’s SWAP™ technology. It is currently being developed for the treatment of retinal vascular-associated diseases. Data generated by Surrozen with SZN-413 in preclinical models of retinopathy demonstrated that SZN-413 could potently stimulate Wnt signaling in the eye, induce normal retinal vessel regrowth, suppress pathological vessel growth and reduce vascular leakage. This novel approach could thus potentially allow for regeneration of healthy eye tissue, not only halting retinopathy, but possibly allowing for a full reversal of the patient’s disease. In the fourth quarter of 2022, Surrozen entered into a strategic partnership with Boehringer Ingelheim for the research and development of SZN-413 for the treatment of retinal diseases. Under the terms of the agreement, Boehringer Ingelheim received an exclusive, worldwide license to develop SZN-413 and other Fzd4-specific Wnt-modulating molecules for all purposes, including as a treatment for retinal diseases, in exchange for an upfront payment to Surrozen of $12.5 million. Surrozen will also be eligible to receive up to $587.0 million in success-based development, regulatory, and commercial milestone payments, in addition to mid-single digit to low-double digit royalties on sales. After an initial period of joint research, Boehringer Ingelheim will assume all development and commercial responsibilities. About Wnt Signaling Wnt signaling plays key roles in the control of development, homeostasis, and regeneration of many essential organs and tissues, including liver, intestine, lung, kidney, retina, central nervous system, cochlea, bone, and others. Modulation of Wnt signaling pathways has potential for treatment of degenerative diseases and tissue injuries. Surrozen’s platform and proprietary technologies have the potential to overcome the limitations in pursuing the Wnt pathway as a therapeutic strategy. About Surrozen Surrozen is a clinical stage biotechnology company discovering and developing drug candidates to selectively modulate the Wnt pathway. Surrozen is developing tissue-specific antibodies designed to engage the body’s existing biological repair mechanisms with a current focus on severe liver and eye diseases. For more information, please visit www.surrozen.com. Forward Looking StatementsThis press release contains certain forward-looking statements within the meaning of the federal securities laws. Forward-looking statements generally are accompanied by words such as “will,” “plan,” “intend,” “potential,” “expect,” “could,” or the negative of these words and similar expressions that predict or indicate future events or trends or that are not statements of historical matters. These forward-looking statements include, but are not limited to, statements regarding Surrozen’s discovery, research and development activities, in particular its development plans for its product candidates SZN-043, and SZN-413 (including anticipated clinical development timelines and the availability of data, the potential for such product candidates to be used to treat human disease), the potential and timeline to nominate the lead development candidate pursuant to its partnership with Boehringer Ingelheim and its expectations with respect to its cash runway. These statements are based on various assumptions, whether or not identified in this press release, and on the current expectations of the management of Surrozen and are not predictions of actual performance. These forward-looking statements are provided for illustrative purposes only and are not intended to serve as, and must not be relied on as a guarantee, an assurance, a prediction, or a definitive statement of fact or probability. Actual events and circumstances are difficult or impossible to predict and will differ from assumptions. Many actual events and circumstances are beyond the control of Surrozen. These forward-looking statements are subject to a number of risks and uncertainties, including the initiation, cost, timing, progress and results of research and development activities, preclinical or and clinical trials with respect to SZN-043, SZN-413 and potential future drug candidates; the Company’s ability to fund its preclinical and clinical trials and development efforts, whether with existing funds or through additional fundraising; Surrozen’s ability to identify, develop and commercialize drug candidates; Surrozen’s ability to successfully complete preclinical and clinical studies for SZN-043, SZN-413, or other future product candidates; the effects that arise from volatility in global economic, political, regulatory and market conditions; and all other factors discussed in Surrozen’s Annual Report on Form 10-K for the year ended December 31, 2022 and Surrozen’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2023 under the heading “Risk Factors,” and other documents Surrozen has filed, or will file, with the Securities and Exchange Commission. If any of these risks materialize or our assumptions prove incorrect, actual results could differ materially from the results implied by these forward-looking statements. There may be additional risks that Surrozen presently does not know, or that Surrozen currently believes are immaterial, that could also cause actual results to differ from those contained in the forward-looking statements. In addition, forward-looking statements reflect Surrozen’s expectations, plans, or forecasts of future events and views as of the date of this press release. Surrozen anticipates that subsequent events and developments will cause its assessments to change. However, while Surrozen may elect to update these forward-looking statements at some point in the future, Surrozen specifically disclaims any obligation to do so, except as required by law. These forward-looking statements should not be relied upon as representing Surrozen’s assessments of any date after the date of this press release. Accordingly, undue reliance should not be placed upon the forward-looking statements. Investor and Media Contact: Investorinfo@surrozen.com

Expect to announce data from SZN-043 Phase 1a clinical trial in patients with chronic liver disease and in healthy volunteers in Q1 2024 Expect to announce data from SZN-1326 Phase 1a clinical trial in healthy volunteers in Q1 2024 Initiating Phase 1b studies in 2024 for SZN-043 in severe alcoholic hepatitis and SZN-1326 in moderate to severe ulcerative colitis Strengthened portfolio through two granted patents from the USPTO related to key discoveries involving the WNT pathway and its modulation Cash, cash equivalents and marketable securities of $43.4 million resulting in cash runway into 2025 SOUTH SAN FRANCISCO, Calif., Nov. 08, 2023 (GLOBE NEWSWIRE) -- Surrozen, Inc. (“Surrozen” or the “Company”) (Nasdaq: SRZN), a company pioneering targeted therapeutics that selectively activate the Wnt pathway for tissue repair and regeneration, today provided third quarter 2023 financial results and business updates. “We look forward to announcing data from the Phase 1a clinical studies for both SZN-043 and SZN-1326 in Q1 2024,” said Craig Parker, President and Chief Executive Officer of Surrozen. “With the significant progress that we made this quarter on the Phase 1a studies, we are looking forward to potentially initiating our Phase 1b studies and providing proof-of-concept data for our lead clinical candidates in 2024. We remain focused on transforming the treatment of severe diseases where Wnt modulation could play an essential role.” Research and Development Pipeline Highlights Phase 1a data from SZN-043 and SZN-1326 primes Company to deliver key 2024 milestones focused on proof-of-concept data SZN-043 Phase 1a study in healthy volunteers and chronic liver disease patients is ongoing and we expect to announce data in Q1 2024We expect to initiate a Phase 1b clinical study in patients with alcoholic hepatitis in 2024 and anticipate proof-of-concept data may be available in the second half of 2024 SZN-1326 Phase 1a study in healthy volunteers is ongoing and we expect to announce data in Q1 2024We expect to initiate a Phase 1b clinical study in patients with ulcerative colitis in 2024 and anticipate proof-of-concept data may be available in the second half of 2024 Corporate Updates Intellectual Property Surrozen has filed or licensed over 20 patent families related to key discoveries involving the WNT pathway and its modulation. In September 2023, Surrozen was granted two of those patents from USPTO - Patents No.: 11/746,150 and 11/773,171 – related to Surrozen’s SZN-1326 clinical candidate and broader SWAP™ technology. Corporate PartnershipsSurrozen executed a partnership with Boehringer Ingelheim (BI) in the fourth quarter of 2022 to develop a Wnt agonist, SZN-413, for the treatment of people with retinal diseases. We anticipate the potential to nominate the lead Fzd-4 targeted Wnt agonist development candidate in 2024, which would trigger a $10.0 million milestone payment to the Company. Financial Results for the Third Quarter Ended September 30, 2023 Cash Position: Cash, cash equivalents and marketable securities were $43.4 million as of September 30, 2023, compared to $53.4 million as of June 30, 2023. Research and Development Expenses: Research and development expenses for the third quarter ended September 30, 2023 were $6.1 million, as compared to $8.6 million for the same period in 2022. The decrease was primarily as a result of the restructuring plans implemented in 2023 to prioritize and focus our resources on clinical stage programs. Research and development expenses include non-cash stock-based compensation expenses of $0.2 million for the third quarter ended September 30, 2023, as compared to $0.4 million for the same period in 2022. General and Administrative Expenses: General and administrative expenses for the third quarter ended September 30, 2023 were $3.6 million, as compared to $5.0 million for the same period in 2022. The decrease was primarily due to the restructuring plans implemented in 2023 and the employee retention tax credits received in 2023. General and administrative expenses include non-cash stock-based compensation expenses of $0.7 million for the third quarter ended September 30, 2023 and 2022. Restructuring: Restructuring charges for the third quarter ended September 30, 2023 were $1.5 million, as compared to zero for the same period in 2022. The increase was attributable to a workforce reduction implemented in the third quarter of 2023. Interest Income: Interest income for the third quarter ended September 30, 2023 was $0.7 million, as compared to $0.2 million for the same period in 2022. The increase was primarily related to an increase in interest rates on money market funds and marketable securities. Other Income, Net: Other income, net for the third quarter ended September 30, 2023 was $83,000, as compared to $50,000 for the same period in 2022. The increase was primarily due to the non-cash change in the fair value of warrant liabilities. Net Loss: Net loss for the third quarter ended September 30, 2023 was $10.4 million, as compared to $13.4 million for the same period in 2022. About SZN-043 for Severe Alcoholic HepatitisSZN-043 is the first development candidate using Surrozen’s SWEETS™ technology. Surrozen is developing SZN-043 for severe liver diseases, initially focusing on severe alcoholic hepatitis. The Company is enrolling patients in a Phase 1a clinical trials in patients with chronic liver disease and healthy volunteers, and the Company expects to announce data in Q1 2024. Surrozen expects to initiate a Phase 1b clinical trial in patients with alcoholic hepatitis in 2024 and anticipates proof-of-concept data may be available in the second half of 2024. About SZN-1326 for Ulcerative ColitisSZN-1326 is the first development candidate designed using Surrozen’s SWAP™ technology and targets the Wnt-signaling pathway in the intestinal epithelium. Surrozen is initially developing SZN-1326 for moderate to severe ulcerative colitis. Enrollment is ongoing in the Phase 1a clinical trial in healthy volunteers, and the Company expects to announce data in Q1 2024. Surrozen also expects to initiate a Phase 1b clinical trial in patients with ulcerative colitis in 2024 and anticipates proof-of-concept data may be available in the second half of 2024. About SZN-413 for Retinal DiseasesSZN-413 is a bi-specific antibody targeting Fzd4-mediated Wnt signaling designed using Surrozen’s SWAP™ technology. It is currently being developed for the treatment of retinal vascular-associated diseases. Data generated by Surrozen with SZN-413 in preclinical models of retinopathy demonstrated that SZN-413 could potently stimulate Wnt signaling in the eye, induce normal retinal vessel regrowth, suppress pathological vessel growth and reduce vascular leakage. This novel approach could thus potentially allow for regeneration of healthy eye tissue, not only halting retinopathy, but possibly allowing for a full reversal of the patient’s disease. In the fourth quarter of 2022, Surrozen entered into a strategic partnership with Boehringer Ingelheim for the research and development of SZN-413 for the treatment of retinal diseases. Under the terms of the agreement, Boehringer Ingelheim received an exclusive, worldwide license to develop SZN-413 and other Fzd4-specific Wnt-modulating molecules for all purposes, including as a treatment for retinal diseases, in exchange for an upfront payment to Surrozen of $12.5 million. Surrozen will also be eligible to receive up to $587.0 million in success-based development, regulatory, and commercial milestone payments, in addition to mid-single digit to low-double digit royalties on sales. After an initial period of joint research, Boehringer Ingelheim will assume all development and commercial responsibilities. About Wnt SignalingWnt signaling plays key roles in the control of development, homeostasis, and regeneration of many essential organs and tissues, including liver, intestine, lung, kidney, retina, central nervous system, cochlea, bone, and others. Modulation of Wnt signaling pathways has potential for treatment of degenerative diseases and tissue injuries. Surrozen’s platform and proprietary technologies have the potential to overcome the limitations in pursuing the Wnt pathway as a therapeutic strategy. About SurrozenSurrozen is a clinical stage biotechnology company discovering and developing drug candidates to selectively modulate the Wnt pathway. Surrozen is developing tissue-specific antibodies designed to engage the body’s existing biological repair mechanisms with a current focus on inflammatory bowel, severe liver and eye diseases. For more information, please visit www.surrozen.com. Forward Looking Statements This press release contains certain forward-looking statements within the meaning of the federal securities laws. Forward-looking statements generally are accompanied by words such as “will,” “plan,” “intend,” “potential,” “expect,” “could,” or the negative of these words and similar expressions that predict or indicate future events or trends or that are not statements of historical matters. These forward-looking statements include, but are not limited to, statements regarding Surrozen’s discovery, research and development activities, in particular its development plans for its product candidates SZN-1326, SZN-043, and SZN-413 (including anticipated clinical development timelines and the availability of data, the potential for such product candidates to be used to treat human disease), the potential and timeline to nominate the lead development candidate pursuant to its partnership with Boehringer Ingelheim and its expectations with respect to its cash runway. These statements are based on various assumptions, whether or not identified in this press release, and on the current expectations of the management of Surrozen and are not predictions of actual performance. These forward-looking statements are provided for illustrative purposes only and are not intended to serve as, and must not be relied on as a guarantee, an assurance, a prediction, or a definitive statement of fact or probability. Actual events and circumstances are difficult or impossible to predict and will differ from assumptions. Many actual events and circumstances are beyond the control of Surrozen. These forward-looking statements are subject to a number of risks and uncertainties, including the initiation, cost, timing, progress and results of research and development activities, preclinical or and clinical trials with respect to SZN-1326, SZN-043, SZN-413 and potential future drug candidates; the Company’s ability to fund its preclinical and clinical trials and development efforts, whether with existing funds or through additional fundraising; Surrozen’s ability to identify, develop and commercialize drug candidates; Surrozen’s ability to successfully complete preclinical and clinical studies for SZN-1326, SZN-043, SZN-413, or other future product candidates; the effects that arise from volatility in global economic, political, regulatory and market conditions; and all other factors discussed in Surrozen’s Annual Report on Form 10-K for the year ended December 31, 2022 and Surrozen’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2023 under the heading “Risk Factors,” and other documents Surrozen has filed, or will file, with the Securities and Exchange Commission. If any of these risks materialize or our assumptions prove incorrect, actual results could differ materially from the results implied by these forward-looking statements. There may be additional risks that Surrozen presently does not know, or that Surrozen currently believes are immaterial, that could also cause actual results to differ from those contained in the forward-looking statements. In addition, forward-looking statements reflect Surrozen’s expectations, plans, or forecasts of future events and views as of the date of this press release. Surrozen anticipates that subsequent events and developments will cause its assessments to change. However, while Surrozen may elect to update these forward-looking statements at some point in the future, Surrozen specifically disclaims any obligation to do so, except as required by law. These forward-looking statements should not be relied upon as representing Surrozen’s assessments of any date after the date of this press release. Accordingly, undue reliance should not be placed upon the forward-looking statements. Investor and Media Contact:Investorinfo@surrozen.com SURROZEN, INC.Condensed Consolidated Statements of Operations(In thousands, except per share amounts)(Unaudited) Three Months Ended Nine Months Ended September 30, September 30, 2023 2022 2023 2022 Operating expenses: Research and development $6,112 $8,624 $21,135 $27,576 General and administrative 3,572 4,981 12,209 14,594 Restructuring 1,505 — 2,712 — Total operating expenses 11,189 13,605 36,056 42,170 Loss from operations (11,189) (13,605) (36,056) (42,170)Interest income 661 198 1,831 307 Other income, net 83 50 96 6,634 Net loss $(10,445) $(13,357) $(34,129) $(35,229) Net loss per share attributable to common stockholders, basic and diluted $(0.34) $(0.38) $(1.13) $(1.01) Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted 30,497 34,968 30,182 34,926 SURROZEN, INC.Condensed Consolidated Balance Sheets(In thousands) September 30, December 31, 2023 2022(1) (Unaudited) Assets Current assets: Cash and cash equivalents $33,975 $24,690 Accounts receivable 1,978 1,978 Short-term marketable securities 9,457 51,148 Prepaid expenses and other current assets 2,947 3,489 Total current assets 48,357 81,305 Property and equipment, net 2,483 3,630 Operating lease right-of-use assets 2,331 3,268 Restricted cash 426 405 Other assets 376 827 Total assets $53,973 $89,435 Liabilities and stockholders’ equity Current liabilities: Accounts payable $287 $658 Accrued and other liabilities 3,953 6,848 Lease liabilities, current portion 2,432 2,226 Total current liabilities 6,672 9,732 Lease liabilities, noncurrent portion 1,527 3,376 Warrant liabilities 243 326 Total liabilities 8,442 13,434 Stockholders’ equity: Preferred stock — — Common stock 3 3 Additional paid-in-capital 258,309 254,892 Accumulated other comprehensive income (loss) 1 (241)Accumulated deficit (212,782) (178,653)Total stockholders’ equity 45,531 76,001 Total liabilities and stockholders’ equity $53,973 $89,435 (1) Derived from the audited financial statements, included in the Company's Annual Report on Form 10-K for the year ended December 31, 2022.

Surrozen has a little over $50 million in cash and equivalents on hand more than two years after reaching Wall Street via a SPAC. Surrozen’s fiscal tightening has continued through the year, with the biotech cutting two preclinical assets to focus on two meds already in trials. The company disclosed Thursday that last month it “implemented a plan to further prioritize and focus resources” on SZN-043 and SZN-1326, extending its cash runway into 2025. The former is in a phase 1 trial for patients with severe alcoholic hepatitis while the latter is being developed to treat moderate to severe inflammatory bowel syndrome.   A snapshot of the company’s pipeline in May via the Internet Archive showed two preclinical assets underway to treat severe dry eye and Fuchs’ dystrophy—both have since been removed. The company did not immediately respond to a question on whether any layoffs will be instigated as a result of the pipeline trim. The company certainly turned to layoffs back in January, when it waved goodbye to 25% of its employees to focus on key clinical and discovery programs. The cost-cutting measures followed a voluntary pause of a phase 1 trial testing SZN-1326 in healthy volunteers disclosed in the third quarter of 2022 after elevated liver enzyme levels were identified in several subjects. The company said at the time that the patients were asymptomatic, but higher-than-normal levels of alanine transaminase and aspartate transaminase can be a sign of liver damage.   Enrollment in that trial did not restart until the second quarter of 2023. Surrozen expects to produce safety data by the end of the year before launching a phase 1b trial in patients with ulcerative colitis in 2024.  Also front of mind for the South San Francisco biotech is making good on its new collaboration with Boehringer Ingelheim, announced in October 2022. Surrozen says it anticipates nominating a lead FZD-4 targeted Wnt agonist drug candidate next year, which would trigger a $10 million milestone payment. Boehringer signed off on more than $580 million in biobucks for the bispecific antibody, SZN-413, in addition to $12.5 million upfront.   Surrozen rode the great SPAC wave of 2021 to Wall Street in a $212 million deal, following two separate $50 million venture rounds. The company now reports having $53.4 million on hand as it tries to strike clinical gold with the existing pipeline.