As filed with the Securities and Exchange Commission on March 31, 2026 Registration No. 333-292829 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 PRE-EFFECTIVE AMENDMENT NO. 1 TO FORM S‑3 ON FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 LeonaBio, Inc. (Exact name of registrant as specified in its charter) (State or other jurisdiction of incorporation or organization) (Primary Standard Industrial Classification Code Number) Delaware 2836 45-3368487 (I.R.S. Employer ...

TO UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 PRE-EFFECTIVE AMENDMENT NO. 1 FORM S‑3 ON FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 LeonaBio, Inc. (Exact name of registrant as specified in its charter) As filed with the Securities and Exchange Commission on March 31, 2026 Registration No. 333-292826 (State or other jurisdiction of incorporation or organization) (Primary Standard Industrial Classification Code Number) Delaware 2836 45-3368487 (I.R.S. Employer ...

Financial Performance - Ligand Pharmaceuticals reported total GAAP revenue of $268 million for 2025, up from $167 million in 2024, with core revenue at $240 million reflecting a 43% year-over-year growth [15][16] - Full-year royalty revenue grew to $161 million, an increase of 48% year-over-year, driven by products such as FILSPARI, Ohtuvayre, CAPVAXIVE, and QARZIBA [15][16] - Adjusted EPS increased to $8.13, up 42% year-over-year, indicating strong operating leverage and higher royalty contributions [15][16] Business Line Performance - FILSPARI's U.S. net sales reached $103 million in Q4, representing 108% growth year-over-year, with total global sales of approximately $355 million for 2025 [16][17] - Ohtuvayre reported net sales of $178 million in Q4, with full-year sales of $506 million, marking a strong launch in COPD history [17][34] - CAPVAXIVE's net sales were $279 million in Q4 and $755 million for the full year, nearing blockbuster status [17][18] Market Performance - Ligand's royalty portfolio is expected to see a 23% compound annual growth rate in royalty receipts from 2025 through 2030, driven by contributions across the entire portfolio [12][13] - The company anticipates significant commercial opportunities in Japan for FILSPARI, with a sizable market for IgAN [71] Company Strategy and Industry Competition - Ligand is focusing on disciplined investments to create new royalty streams and enhance long-term shareholder value, with a systematic portfolio management strategy to drive value across partnerships [9][10][22] - The demand for royalty financing has doubled over the last five years, positioning Ligand favorably within the biopharmaceutical royalty financing sector [10][11] Management Commentary on Operating Environment and Future Outlook - Management expressed confidence in the company's growth trajectory, citing strong trial results for QTORIN rapamycin and the successful partnership with Leona Bio for lasofoxifene [36] - The company is optimistic about the upcoming year, expecting multiple catalysts from its late-stage development pipeline [36][31] Other Important Information - Ligand ended 2025 with $734 million in cash equivalents and short-term investments, totaling over $1 billion in deployable capital [20] - The company reaffirmed its 2026 financial guidance, expecting adjusted EPS of approximately $8-$9 per share and royalty revenue of $200 million-$225 million [20][21] Q&A Session Summary Question: Clinical update expectations for late-stage royalty portfolio - Management highlighted several active late-stage programs, including QARZIBA and TZIELD, with robust updates expected in the coming quarters [39][40] Question: Update on monetizing older assets in the portfolio - Management confirmed active engagement in 5 to 10 opportunities for older assets, with potential announcements expected by year-end [43][44] Question: Larger opportunity for TZIELD and peak sales size - Management acknowledged TZIELD's low royalty but emphasized its potential blockbuster status, particularly with the upcoming Stage 3 indication [48][50] Question: Impact of FSGS approval delay on 2026 outlook - Management indicated that the FSGS contribution to 2026 guidance is modest, with a risk-adjusted estimate of $4 million [53][55] Question: Changes in selection criteria for potential partnerships - Management noted that as the portfolio value grows, the average deal size will increase, focusing on high clinical value assets [58][59]

Financial Data and Key Metrics Changes - Full-year adjusted EPS exceeded original 2025 guidance by more than 30%, with a 42% increase year-over-year [6][7] - Total GAAP revenue for 2025 was $268 million, up from $167 million in 2024, with core revenue reflecting a 43% year-over-year growth at $240 million [15][16] - Royalty revenue grew to $161 million, an increase of 48% year-over-year, driven by products like FILSPARI, Ohtuvayre, CAPVAXIVE, and QARZIBA [15][16] Business Line Data and Key Metrics Changes - FILSPARI's U.S. net sales reached $103 million in Q4, representing 108% growth year-over-year, with total annual sales of $322 million [16][17] - Ohtuvayre reported U.S. net sales of $506 million for the full year 2025, with Q4 sales just under $200 million [17] - CAPVAXIVE's net sales were $279 million in Q4 and $755 million for the full year, nearing blockbuster status [17] Market Data and Key Metrics Changes - The royalty funding market has doubled over the last five years, indicating a growing demand for royalty capital [10][11] - Ligand expects a 23% compound annual growth rate in royalty receipts from 2025 through 2030, driven by contributions across the entire portfolio [12][13] Company Strategy and Development Direction - Ligand is focused on disciplined investments to create new, clinically differentiated product royalty streams and enhance long-term shareholder value [8][9] - The company launched a systematic portfolio management strategy to proactively communicate with partners and identify new investment opportunities [22][23] - Ligand aims to expand its business development efforts and deepen its pipeline, with a strong capital base to support growth initiatives [10][11] Management's Comments on Operating Environment and Future Outlook - Management expressed confidence in the continued momentum of the royalty portfolio and disciplined capital deployment approach, positioning the company for sustained long-term growth [12][13] - The company anticipates significant commercial upside from products like FILSPARI and Ohtuvayre, with ongoing efforts to engage with regulatory bodies for approvals [34][35] Other Important Information - Ligand ended 2025 with $734 million in cash equivalents and short-term investments, totaling over $1 billion in deployable capital [20] - The company is optimistic about the potential of lasofoxifene and QTORIN rapamycin, with significant market opportunities projected [24][29] Q&A Session Summary Question: Clinical update expectations for late-stage royalty portfolio - Management highlighted several active late-stage programs, including QARZIBA and TZIELD, with robust updates expected in the coming quarters [39][40] Question: Update on monetizing older assets in the portfolio - Management confirmed active engagement in 5 to 10 opportunities for older assets, with potential announcements expected by year-end [43][44] Question: Larger opportunity for TZIELD and peak sales size - Management acknowledged TZIELD's low royalty but emphasized its potential blockbuster status, particularly with the upcoming Stage 3 indication [48][49] Question: Impact of FSGS approval delay on 2026 outlook - Management indicated that the FSGS contribution to 2026 guidance is modest, with a risk-adjusted estimate of $4 million [53][55] Question: Changes in selection criteria for potential partnerships - Management noted that as the portfolio value grows, the average deal size sought will increase, focusing on high clinical value assets [58][59] Question: Market size opportunity for FILSPARI in IgAN and FSGS - Management estimated consensus market size for both indications at around $1 billion, with potential royalties of approximately $90 million for each [70][71]

Financial Performance - In 2025, Ligand Pharmaceuticals achieved total GAAP revenue of $268 million, up from $167 million in 2024, with core revenue at $240 million reflecting a 43% year-over-year growth [12][13] - Full-year adjusted EPS increased to $8.13, a 42% rise year-over-year, driven by strong operating leverage and higher royalty contributions [13][10] - Royalty revenue grew to $161 million, marking a 48% increase year-over-year, primarily from FILSPARI, Ohtuvayre, CAPVAXIVE, and QARZIBA [12][5] Business Line Performance - FILSPARI's U.S. net sales reached $103 million in Q4, representing 108% growth year-over-year, with total global sales of approximately $355 million for 2025 [13][14] - Ohtuvayre reported U.S. net sales of $506 million for the full year 2025, with Q4 sales of nearly $200 million [14] - CAPVAXIVE's net sales were $279 million in Q4 and $755 million for the full year, nearing blockbuster status [15] Market Data - The royalty financing market has doubled over the last five years, indicating a growing demand for royalty capital [9] - Ligand expects a compound annual growth rate of 23% in royalty receipts from 2025 through 2030, driven by contributions across its portfolio [10] Company Strategy and Industry Competition - Ligand is focusing on disciplined investments to create new royalty streams and enhance long-term shareholder value, with a strong emphasis on proactive portfolio management [6][19] - The company is positioned uniquely within the biopharmaceutical royalty financing sector, capitalizing on high demand for capital [9] Management Commentary on Operating Environment and Future Outlook - Management expressed confidence in the continued momentum of the royalty portfolio and the disciplined capital deployment approach, which positions the company for sustained long-term growth [11][33] - The company anticipates a strong pipeline of late-stage development programs and is optimistic about upcoming regulatory decisions and market expansions [33][27] Other Important Information - Ligand ended 2025 with $734 million in cash equivalents and short-term investments, totaling over $1 billion in deployable capital [17] - The company is actively engaged in monetizing older assets and exploring new investment opportunities across its portfolio [41][42] Q&A Session Summary Question: Clinical update expectations for late-stage royalty portfolio - Management highlighted several active late-stage programs, including QARZIBA and Lasofoxifene, with robust updates expected in the coming quarters [37] Question: Update on monetizing older assets - Management confirmed ongoing engagement with 5 to 10 opportunities for monetization and expects announcements by year-end [41] Question: Market opportunity for TZIELD - Management acknowledged the low royalty but emphasized the potential blockbuster opportunity with Sanofi's TZIELD, particularly in Stage 3 Type 1 diabetes [46] Question: Impact of FSGS approval delay on 2026 outlook - Management indicated that the FSGS approval delay would have a negligible impact on the 2026 guidance, with a modest $4 million contribution assumed [51][63] Question: Differentiation of Castle Creek technology - Management discussed the potential advantages of the Castle Creek treatment over competitors, emphasizing its injectable nature and broader application [58]

Core Insights - LeonaBio, Inc. has appointed Mark F. Kubik as Chief Business Officer to lead its business development strategy, focusing on licensing, partnership strategy, and corporate development initiatives [1][3] Company Overview - LeonaBio is a clinical-stage biopharmaceutical company based in Bothell, Washington, dedicated to developing novel therapeutics for diseases with high unmet medical needs, including treatment-resistant metastatic breast cancer and amyotrophic lateral sclerosis (ALS) [10] Leadership Appointment - Mark F. Kubik brings over 25 years of biopharma business development and corporate strategy experience, having previously served as a strategic consultant to LeonaBio [2][4] - His appointment is seen as pivotal for advancing the Phase 3 development of lasofoxifene for metastatic breast cancer and building a diversified pipeline in oncology and neurodegeneration [3] Strategic Vision - Mr. Kubik expressed excitement about joining LeonaBio at a critical juncture, emphasizing the urgency of advancing lasofoxifene as a therapeutic candidate for treatment-resistant metastatic breast cancer [3] - The company aims to expand its portfolio and explore strategic collaborations under his leadership [3] Inducement Stock Option - LeonaBio announced an equity inducement award to Mr. Kubik, granting him stock options to purchase 30,000 shares at an exercise price of $4.74, effective from February 1, 2026 [6][7] - The vesting schedule includes one-fourth of the shares vesting on the first anniversary and one forty-eighth each month thereafter, contingent on continued service [8] Educational Background - Mr. Kubik holds an MBA in Finance and a BA in Molecular, Cellular and Developmental Biology from the University of Colorado, Boulder, and has completed Executive Education in Negotiation and Influence Strategies at Stanford University [5]

Core Viewpoint - Athira Pharma, Inc. has rebranded as LeonaBio, Inc. to reflect its strategic focus on developing lasofoxifene for metastatic breast cancer treatment, currently in Phase 3 trials [1][2] Company Overview - LeonaBio is a clinical-stage biopharmaceutical company focused on innovative therapeutics for diseases with high unmet medical needs, including metastatic breast cancer and amyotrophic lateral sclerosis (ALS) [10] - The company aims to advance a pipeline of late-stage assets to maximize clinical and commercial impact [2] Name and Ticker Change - The name change to LeonaBio symbolizes strength and resilience, aligning with the company's mission to support patients facing serious diseases [2] - The new ticker symbol "LONA" will be effective on January 12, 2026, on The Nasdaq Capital Market [1] Lead Drug Candidates - Lasofoxifene and ATH-1105 are the lead drug candidates, targeting treatment-resistant metastatic breast cancer and ALS, respectively [3][10] - Lasofoxifene is in a Phase 3 trial (ELAINE-3) with over 50% enrollment, and data is expected in mid-2027 [3][6] Licensing and Financing - LeonaBio secured an exclusive global license for lasofoxifene from Sermonix Pharmaceuticals, excluding Asia and certain Middle Eastern countries [4] - The company raised $90 million through a private placement, with potential additional funding of up to $146 million from warrants, to support lasofoxifene's development [4] Drug Candidate Details - Lasofoxifene is a selective estrogen receptor modulator (SERM) designed to target both wild-type and mutant estrogen receptors, addressing a critical unmet need in metastatic breast cancer [5] - ATH-1105 is a next-generation small molecule aimed at treating neurodegenerative diseases, currently in Phase 1 trials with plans for a Phase 2 trial in ALS patients in early 2026 [7][8]

Core Viewpoint - Athira Pharma, Inc. has rebranded as LeonaBio, Inc. following the acquisition of rights to develop and commercialize lasofoxifene for metastatic breast cancer, reflecting the company's commitment to innovation and leadership in addressing unmet medical needs [1][2] Group 1: Company Name Change and Strategy - The name change to LeonaBio symbolizes strength and resilience, aligning with the company's mission to deliver transformative therapies for serious diseases [2] - The new ticker symbol "LONA" will be used on The Nasdaq Capital Market starting January 12, 2026, without affecting the company's legal structure or operations [1][2] Group 2: Drug Development Focus - LeonaBio's lead drug candidates include lasofoxifene and ATH-1105, targeting treatment-resistant metastatic breast cancer and amyotrophic lateral sclerosis (ALS) [3][9] - Lasofoxifene is currently in a Phase 3 clinical trial (ELAINE-3), with over 50% enrollment and data expected in mid-2027 [3][6] Group 3: Licensing and Financing - The company secured an exclusive global license for lasofoxifene from Sermonix Pharmaceuticals, with an upfront financing of $90 million and potential additional funding of up to $146 million through warrants [4] - This financing is expected to support lasofoxifene's development through key clinical and regulatory milestones, with sufficient capital for operations into 2028 [4] Group 4: Drug Candidate Details - Lasofoxifene is a selective estrogen receptor modulator (SERM) designed to target both wild-type and mutant estrogen receptors, addressing critical unmet needs in metastatic breast cancer [5] - ATH-1105 is a next-generation small molecule drug candidate aimed at treating neurodegenerative diseases, currently in clinical development for ALS [7][8]

Core Viewpoint - Athira Pharma Inc. is making significant strides in its development pipeline by acquiring rights to lasofoxifene, a drug in a Phase 3 trial for metastatic breast cancer, which is expected to enhance its market position and growth potential [1][2]. Group 1: Acquisition Details - Athira has secured an exclusive global license (excluding Asia and certain Middle Eastern countries) from Sermonix Pharmaceuticals for the development and commercialization of lasofoxifene [2]. - As part of the agreement, Athira will issue a pre-funded warrant to purchase approximately 5.5 million shares at an exercise price of $0.001 per share, along with potential payments of up to $100 million based on commercialization or annual net sales milestones [3]. Group 2: Financing and Development Plans - The company announced a $90 million upfront financing through private placement of common stock and warrants, which could provide an additional $146 million if the warrants are exercised, aimed at supporting the development of lasofoxifene through key clinical and regulatory milestones [4]. - The net proceeds from the financing will be utilized for the development of lasofoxifene for treatment-resistant metastatic breast cancer, other clinical assets, and general corporate purposes [5]. Group 3: Market Performance - Following the announcement, Athira Pharma's stock surged by 74.49% to $7.22, reaching a new 52-week high, indicating strong market confidence in the company's future prospects [5].

Core Viewpoint - Athira Pharma, Inc. announced an agreement to acquire global development and commercialization rights to lasofoxifene, a Phase 3 ready asset for metastatic breast cancer, leading to a significant surge in its stock price [1] Group 1: Stock Performance - Athira Pharma shares surged 69.53 percent, gaining $2.88 to trade at $7.01 on Thursday [1] - The stock opened at $7.22 and fluctuated within a day's range of $6.77 to $8.35 [2] - Trading volume spiked to approximately 53.19 million shares, significantly higher than the average volume of around 30,063 shares [2] Group 2: Market Reaction - Investors reacted positively to the late-stage pipeline expansion, with shares now trading near the top of its 52-week range of $2.20 to $8.35 [2]