CURIS INC

Item 1A. RISK FACTORS

We are subject to a number of risks that could materially and adversely affect our business, financial condition, and results of operations and future prospects, including those identified in Item 1A, Risk Factors of Part I of our Annual Report on Form 10-K for the year ended December 31, 2024, which was filed with the SEC on March 31, 2025, and the updated risk factors set forth below.

Changes in We are not in compliance with the requirements for continued listing on the Nasdaq Capital Market. If we fail to regain and maintain compliance with Nasdaqs requirements, our common stock could be delisted from trading, which would decrease the liquidity of our common stock and uncertainty surrounding our ability to raise additional capital.

Our common stock is currently listed on the Nasdaq Capital Market. We are required to meet specified requirements to maintain our listing on the Nasdaq Capital Market, including a minimum bid price of $1.00 per share for our common stock and standards relative to minimum stockholders equity, minimum market value of publicly held shares and various additional requirements. In the past we have, from time to time, received deficiency letters from Nasdaq as a consequence of our failure to satisfy such requirements. On February 21, 2025, we received a deficiency letter from Listing Qualifications Department of Nasdaq notifying us that the market value of our listed securities had closed for the last 30 consecutive business days below the minimum $35,000,000 requirement for continued listing on the Nasdaq Capital Market pursuant to Nasdaq Listing Rule 5550(b)(2), or Minimum MVLS Requirement. We have 180 calendar days, or until August 20, 2025, or Compliance Period, to regain compliance with the Minimum MVLS Requirement. In order to regain compliance, during the Compliance Period, the market value of our listed securities must close at $35,000,000 or more for a minimum of ten consecutive business days. If we do not regain compliance within the Compliance Period, we will receive written notification that our securities are subject to delisting from the Nasdaq Capital Market. At that time, we expect to appeal the delisting determination to a hearings panel pursuant to the procedures set forth in the applicable Nasdaq Listing Rules. The outcome of any such Nasdaq process is inherently uncertain. There can be no assurance that we can regain, or maintain in the future, compliance with the Nasdaq continued listing requirements.

If we fail to satisfy the Nasdaq Capital Markets continued listing requirements and we are delisted from Nasdaq, we may transfer to and commence trading on the OTC Markets or another quotation medium. As a result, an investor would likely find it more difficult to trade or obtain accurate price quotations for our shares. Delisting would likely also reduce the visibility, liquidity, and value of our common stock, could have a material adverse effect on our access to capital markets and our ability to raise capital on terms acceptable to us, or at all, to provide stock-based incentives to attract and retain personnel, reduce institutional investor interest in our company, and may increase the volatility of our common stock. Delisting could also be considered a material adverse event or an event of default in certain of our third-party contracts or cause a loss of confidence of potential industry partners, lenders, and employees, which could further harm our business and our future prospects. In addition, our common stock could be deemed to be a penny stock, which could result in reduced levels of trading in our common stock, and we would also become subject to additional state securities regulations in connection with any sales of our securities. Some or all of these material adverse consequences may contribute to a further decline in our stock price.

Changes in and uncertainty surrounding U.S. trade policy could have a material adverse impact on our business, financial condition and results of operations.

We rely on third party contract manufacturing organizations, or CMOs, to produce our product candidate. One of our CMOs has a Chinese subcontractor that produces regulatory starting materials. Another CMO operates in Canada and produces our drug product. This past spring, the Trump Aadministration has recently imposinitiated a series of tariffs on -related actions against U.S. trading partners. On April 2, 2025, the President issued an Eexecutive O\order announcing a baseline reciprocal tariff of 10% on all U.S. trading partners effective April 5, 2025, and higher individualized reciprocal tariffs on 57 countries (with certain product exemptions for pharmaceutical-related products, among others). Previously, the administration had imposed a 25% tariff on Canada and Mexico for goods not covered by the United States-Mexico-Canada Agreement, or USMCA, and tariffs equaling

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20% on China. In response, several countries threatened retaliatory measures, including Canada and China, which then imposed retaliatory tariffs. Prior to when the country-specific reciprocal tariffs were scheduled to take effect, the administration delayed the effective date of such tariffs for all countries except China. TLater, the 10% baseline rU.S. and China reached a framework agreement that resulted in the suspension of the higher reciprocal tariffs on all China until August 10, 2025. Three other countries remains in e, the United Kingdom, Vietnam and Indonesia, have also reached deals with the US that include reduced tariff rates and other measures. The administration has not indicated the effect, in additive date for these deals. Recently, the administration announced an extension toof the deadline for the tariffs on China (which were a effective date of the country-specific tariffs for all remaining countries until August 1, 2025.

Currently, the 10% baseline reciprocal tariff announced in April remains in effect, in addition to the other tariffs on China (a minimum of 145an additional 20% as of April 21July 15, 2025) and Canada and Mexico (which were 25% as of April 21July 15, 2025 for

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goods that are not covered by the USMCA). Sustained uncertainty about, or the further escalation of, trade and political tensions between the United States and China could result in a disadvantageous research and manufacturing environment in China and Canada, particularly for U.S. based companies, including retaliatory restrictions that hinder or potentially inhibit our ability to rely on contract development and manufacturing organizations and other service providers that operate in China.

Separately, on April 16, 2025, the U.S. Department of Commerce announced an investigation under Section 232 of the Trade Expansion Act of 1962 into imports of pharmaceuticals and pharmaceutical ingredients, including finished drug products, medical countermeasures, critical inputs such as active pharmaceutical ingredients, and key starting materials, and derivative products of those items. The investigation will examine the impact of these imports on U.S. national security culminating in a decision by the President whether to take action to remedy any identified threats, including by imposing additional tariffs. The statute provides that the U.S.Commerce Department of Commerce rereport must be completed within 270 days of initiation of the investigation and that the President must decide whether to act within 90 days of receiving the report.

As a result of changes in tariffs that have been announced and/or implemented, and the underlying uncertainty currently surrounding international trade, we could experience a negative impact to our costs of materials and production processes, and supply chain disruptions and delays as a result of any new tariff policies or trade restrictions. If we are unable to obtain necessary raw materials or product components in sufficient quantity and in a timely manner from China, Canada, or other countries due due to disruptions in the global supply chain caused by macroeconomic events and conditions, the development, testing and clinical trials of our product candidate may be delayed or infeasible, and regulatory approval or commercial launch of any resulting product may be delayed or not obtained, which could significantly harm our business. We cannot yet predict the effect of the recently imposed U.S. tariffs on imports, or the extent to which other countries will impose quotas, duties, tariffs, taxes or other similar restrictions upon imports or exports in the future, nor can we predict future trade policy or the terms of any renegotiated trade agreements and their impact on our business.

Disruptions at the FDA and other government agencies from funding cuts, personnel losses, regulatory reform, government shutdowns and other developments could hinder our ability to obtain guidance from the FDA regarding our clinical development program and develop and secure approval of our product candidates in a timely manner, which would negatively impact our business.

The U.S. Food and Drug Administration, or FDA, and comparable regulatory agencies in foreign jurisdictions, such as the European Medicines Agency, or EMA, and the EMAs Committee for Medicinal Products for Human Use, play an important critical role in the development of our product candidates by providing guidance on our clinical development programs and reviewing oand approving our regulatory submissions, including investigational new drug applications, or INDs, requests for special designations and marketing applications. If these oversight and review activities are disrupted or delayed or previous alignment with the agencies is changed, then correspondingly our ability to develop and secure timely approval of our product candidates could be impacted in a negative manner.

For example, the recent loss of FDA leadership and personnel could lead to disruptions and delays in FDA guidance, review and approval of our product candidates. Pursuant to President Trump's E.O. 14210, Implementing the Presidents Department of Government Efficiency Workforce Optimization Initiative, the Secretary of the Department of Health and Human Services, or HHS, announced on March 27, 2025, a reorganization and Reduction in Force, or RIF, across HHS of approximately 20,000 employees (82,000 to 62,000), with FDAs workforce tof approximately 20,000 to decrease by 3,500 full-time employees. Shorubsequently, thereafter, FDA indicated thousands at roughly a quarter of ethose employees at the FDA were fired on April 1who received RIF notices had been reinstated. On July 14, 2025. Subsequently, following litigation reaching the US Supreme Court, there have administration been reports from gan to carry out these layoffs across HHS, including the preliminary budget memorandum for HHS thatFDA. There are also ongoing deliberations within the administration will propose an additionand Congress over potentially substantial 30%proposed cut ins to the overall budget for HHS, with a reduction of $700 million in f and funding atof the FDA ($7.2 billion to $6.5 billion) for the 2026 federal fiscal year.

Further, while the FDAs review of marketing applications and other activities for new drugs and biologics is largely funded through the user fee program established under the Prescription Drug User Fee Act, or PDUFA, it remains unclear how the administrations RIF and budget cuts will impact this program and the ability of the FDA to provide guidance and review

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our product candidates in a timely manner. For example, while the FDA RIF did not reportedly specifically target FDA reviewers, many operations, administrative and policy staff that help support such reviews were affected and those losses could lead to delays in PDUFA reviews and related activities. As of July 15, 2025, there has been at least one report in which the FDA failed to meet a PDUFA goal date for approval of an NDA due to heavy workload and limited resources. In addition, while currently unclear, there is a risk that the RIF and budget cutbacks could threaten the integrity of the PDUFA program itself. That is because, for the FDA to obligate user fees collected under PDUFA in the first place, a certain amount of non-user fee appropriations must be spent on the process for the review of applications plus certain other costs during the same fiscal year.

There is also substantial uncertainty as to how regulatory reform measures being implemented by the Trump Administration across the government will impact the FDA and other federal agencies with jurisdiction over our activities. For example, since taking office, the President has issued a number of executive orders that could have a significant impact on the manner in which the FDA conducts its operations and engages in regulatory and oversight activities. These include E.O. 14192, Unleashing Prosperity Through Deregulation, January 31, 2025; E.O. 14212, Establishing the Presidents Make America Healthy Again Commission, February 13, 2025; and E.O. 14219, Ensuring Lawful Governance and Implementing the Presidents Department of Government Efficiency Deregulatory Initiative, February 21, 2025. If these or other orders or

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executive actions impose constraints on the FDAs ability to engage in oversight and implementation activities in the normal course, our business may be negatively impacted.

Similarly, actions by the U.S. government have significantly disrupted the operations of U.S. government agencies such as the National Institutes of Health, National Science Foundation, Centers for Disease Control and Prevention, and FDA, which have traditionally provided funding for basic research, research and development, and clinical testing. These U.S. government actions have included, among other things, suspending, terminating and withholding of disbursements of funds owed under ongoing contracts, grants, and other financial assistance agreements; declining to continue multi-year research projects for additional annual budget periods; canceling or delaying solicitations for new contract, grant and other financial assistance awards; canceling or delaying proposal evaluation processes and issuance of such new awards; substantially reducing federal agency staff responsible for managing contract and financial assistance programs; eliminating agency information and resources for facilitating research activity; delaying or terminating federal agency procedures for authorizing international transactions; initiating aggressive enforcement actions that may disrupt the operations of major research universities that are significant contributors to life sciences research in the U.S., and threatening access to federal agency contracts and other funding awards based on companies otherwise lawful corporate policies and choice of counsel. These U.S. government actions could, directly or indirectly, significantly disrupt, delay, prevent, or increase the costs of our research and product commercialization programs, including our ability to develop new product candidates, conduct clinical trials, implement research collaborations with other companies or institutions, and obtain approvals to market and sell new products.

In addition, government funding of the Securities and Exchange Commission, or SEC, and other government agencies on which our operations may rely, including those that fund research and development activities, is subject to the political process, which is inherently fluid and unpredictable. For example, over the last several years, the U.S. government has shut down several times and certain regulatory agencies, such as the FDA and the SEC, have had to furlough critical FDA, SEC and other government employees and stop critical activities. If a prolonged government shutdown occurs, it could significantly impact the ability of the FDA to timely review and process our regulatory submissions and could impact our ability to access the public markets and obtain necessary capital in order to properly capitalize and continue our operations.

At the same time, disruptions at the FDA and other government agencies may result from public health events similar to the COVID-19 pandemic. For example, during the pandemic, a number of companies announced receipt of complete response letters due to the FDAs inability to complete required inspections for their applications. In the event of a similar public health emergency in the future, the FDA may not be able to continue its current pace and review timelines could be extended. Regulatory authorities outside the United States facing similar circumstances may adopt similar restrictions or other policy measures in response to a similar public health emergency and may also experience delays in their regulatory activities.

Accordingly, if any of the foregoing developments and others impact the ability of the FDA to provide us with guidance regarding our clinical development programs or delay the agencys review and processing of our regulatory submissions, including INDs and new drug applications/biologics license applications, our business would be negatively impacted. Further, any future government shutdown could impact our ability to access the public markets and obtain necessary capital in order to properly capitalize and continue our operations.

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