This prospectus supplement amends and supplements the information in the prospectus dated August 6, 2025, filed as part of the registration statement on Form S-3 (File No. 333-289326). It should be read in conjunction with the ATM Prospectus, with the exception that the information herein amends or supersedes the information contained in the ATM Prospectus. The prospectus supplement is not complete without the ATM Prospectus and may only be delivered or utilized in connection with it and any future amendments or supplements thereto.
The company has entered into an amended and restated sales agreement with Leerink Partners LLC and Cantor Fitzgerald & Co. as sales agents. Under this agreement, the company may issue and sell American Depositary Shares (ADSs), each representing three ordinary shares, with a par value of $0.0001 per share. The maximum aggregate gross offering amount of ADSs that the company may offer and sell has been increased to $400,000,000. As of the date of this prospectus supplement, the company has sold approximately $58.5 million (3,040,000 ADSs) pursuant to the sales agreement, leaving a remaining capacity to sell up to $341,478,784.
The ADSs are listed on the Nasdaq Global Market under the symbol “GPCR.” On May 6, 2026, the last reported sale price of the ADSs was $40.84 per ADS. Sales of the ADSs, together with the underlying ordinary shares, may be made in sales deemed to be an "at-the-market offering" as defined in Rule 415(a)(4) under the Securities Act of 1933, as amended. The sales agents are not required to sell any specific number or dollar amount of securities but will act as sales agents using commercially reasonable efforts consistent with their normal trading and sales practices, on mutually agreed terms among the sales agents and the company. There is no arrangement for funds to be received in any escrow, trust, or similar arrangement.
The sales agents will be entitled to a commission of up to 3.0% of the gross proceeds of any ADSs sold under the amended and restated sales agreement. In connection with the sale of the ADSs on behalf of the company, the sales agents will each be deemed to be an "underwriter" within the meaning of the Securities Act, and their compensation will be deemed to be underwriting commissions or discounts. The company has also agreed to provide indemnification and contributions to the sales agents against certain civil liabilities, including liabilities under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended.
Investing in the ADSs involves a high degree of risk. Investors should review carefully the risks and uncertainties described in the section titled "Risk Factors" beginning on page S-4 of the ATM Prospectus, and under similar headings in the documents that are incorporated by reference into this prospectus supplement and the ATM Prospectus concerning factors investors should consider before investing in the ADSs.
Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities, or passed upon the adequacy or accuracy of the disclosures in this prospectus supplement or the ATM Prospectus. Any representation to the contrary is a criminal offense.
The plan of distribution outlines the terms and conditions of the sales agreement, including the method of sales, the compensation to be paid to the sales agents, and the reporting requirements. The sales agents will offer the ADSs subject to the terms and conditions of the sales agreement on a daily basis or as otherwise agreed upon by the company and the sales agents. The company will designate the maximum number or amount of ADSs to be sold through the sales agents on a daily basis or otherwise determine such maximum number or amount together with the sales agents.
The compensation payable to the sales agents will be an amount of up to 3.0% of the gross proceeds of any ADSs sold through it pursuant to the sales agreement. The company has also agreed to reimburse the sales agents for certain of their expenses in an amount up to $100,000, in addition to certain ongoing disbursements of their legal counsel in the amount up to $25,000 in connection with certain events described in the sales agreement. The company estimates that the total expenses of the offering payable by it, excluding compensation payable to the sales agents under the sales agreement, will be approximately $1.1 million.
Settlement for sales of ADSs will occur, unless the parties agree otherwise, on the first trading day following the date on which any sales were made in return for payment of the net proceeds to the company. There is no arrangement for funds to be received in an escrow, trust, or similar arrangement. The company will report at least biannually the number of ADSs sold through the sales agents under the sales agreement, the net proceeds to the company, and the compensation paid by the company to the sales agents in connection with the sales of ADSs during the relevant period.
In connection with the sale of the ADSs on behalf of the company pursuant to the sales agreement, the sales agents will each be deemed to be an "underwriter" within the meaning of the Securities Act and the compensation paid to each sales agent will be deemed to be underwriting commissions or discounts. The sales agents and/or their affiliates have provided, and may in the future provide, various investment banking and other financial services for the company for which services they have received, and may in the future receive, customary fees.
Up to $400,000,000
American Depositary Shares representing Ordinary Shares
This prospectus supplement amends and supplements the information in our prospectus dated August6,2025, (ATM Prospectus), filed as part of our registration statement on Form S-3 (File No. 333-289326). Thisprospectus supplement should be read in conjunction with the ATM Prospectus, and is qualified by referencethereto, except to the extent that the information herein amends or supersedes the information contained inthe ATM Prospectus. This prospectus supplement is not complete without, and may only be delivered orutilized in connection with, the ATM Prospectus, and any future amendments or supplements thereto.
We previously entered into a Sales Agreement (sales agreement) with Leerink Partners LLC and CantorFitzgerald & Co., each of whom we refer to as a sales agent, and together as the sales agents, relating toAmerican Depositary Shares (ADSs), each representing three ordinary shares, $0.0001 par value perordinary share, offered by the ATM Prospectus. On May7, 2026, we amended and restated the salesagreement (as amended and restated, the amended and restated sales agreement) to remove the aggregateoffering amount thereunder. We are filing this prospectus supplement to amend the ATM Prospectus toincrease the maximum amount of ADSs we may offer and sell in accordance with the terms of the amendedand restated sales agreement to an aggregate gross offering amount of $400,000,000. As of the date of thisprospectus supplement, we have sold approximately $58.5million (3,040,000 ADSs) pursuant to the salesagreement, and, after giving effect to this prospectus supplement, have a remaining capacity to sell up to$341,478,784.
Our ADSs are listed on the Nasdaq Global Market under the symbol “GPCR.” On May6, 2026, the lastreported sale price of our ADSs as reported on the Nasdaq Global Market was $40.84 per ADS.
Sales of our ADSs, together with the underlying ordinary shares, if any, under this prospectus supplementand the ATM Prospectus may be made in sales deemed to be an “at-the-market offering” as defined inRule415(a)(4) promulgated under the Securities Act of 1933, as amended (Securities Act). The sales agentsare not required to sell any specific number or dollar amount of securities but will act as our sales agentsusing commercially reasonable efforts consistent with their normal trading and sales practices, on mutuallyagreed terms among the sales agents and us. There is no arrangement for funds to be received in anyescrow, trust or similar arrangement.
The sales agents will be entitled to a commission of up to 3.0% of the gross proceeds of any ADSs sold underthe amended and restated sales agreement. In connection with the sale of our ADSs on our behalf, the salesagents will each be deemed to be an “underwriter” within the meaning of the Securities Act and theircompensation will be deemed to be underwriting commissions or discounts. We have also agreed to provideindemnification and contributions to the sales agents against certain civil liabilities, including liabilities underthe Securities Act and the Securities Exchange Act of 1934, as amended. See “Plan of Distribution” beginningon pageS-1for additional information regarding the compensation to be paid to the sales agents.
Investing in our ADSs involves a high degree of risk. You should review carefully the risksand uncertainties described in the section titled “Risk Factors” beginning on page S-4 ofthe ATM Prospectus, and under similar headings in the documents that are incorporated byreference into this prospectus supplement and the ATM Prospectus concerning factors youshould consider before investing in our ADSs.
Neither the Securities and Exchange Commission nor any state securities commission hasapproved or disapproved of these securities, or passed upon the adequacy or accuracy ofthe disclosures in this prospectus supplement or the ATM Prospectus. Any representationto the contrary is a criminal offense.
Leerink Partners
Cantor
The date of this prospectus supplement is May7, 2026
PLAN OF DISTRIBUTION
We have entered into the amended and restated sales agreement with Leerink Partners LLC and CantorFitzgerald & Co., each of whom we refer to as a sales agent, and together the sales agents, under which wemay issue and sell our ADSs, each representing three of our ordinary shares, par value US$0.0001 pershare, from time to time through the sales agents. Sales of the ADSs, if any, will be made by any method thatis deemed to be an “at the market offering” as defined in Rule415 under the Securities Act, including salesmade directly on or through the Nasdaq Global Market, on or through any other existing trading market forour ADSs or to or through a market maker or otherwise, through block transactions and/or any other methodpermitted by law, in each case at market prices.
The sales agents will offer the ADSs subject to the terms and conditions of the sales agreement on a dailyb
