Spero Therapeutics Receives $25 Million Milestone Payment Triggered by GSK's NDA Submission
Written by Emily J. Thompson, Senior Investment Analyst
Updated: Dec 19 2025
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Should l Buy GSK?
Spero Therapeutics (SPRO) announced that its development partner, GSK (GSK), filed a New Drug Application, NDA, resubmission to the U.S. Food and Drug Administration, FDA, for tebipenem HBr, an investigational oral carbapenem antibiotic being developed for the treatment of complicated urinary tract infections, cUTI, including pyelonephritis. The NDA submission triggers a $25 million milestone payment to Spero, expected to be received in Q1 2026.
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Analyst Views on GSK
Wall Street analysts forecast GSK stock price to fall
6 Analyst Rating
1 Buy
2 Hold
3 Sell
Moderate Sell
Current: 52.950
Low
20.15
Averages
38.72
High
55.60
Current: 52.950
Low
20.15
Averages
38.72
High
55.60
About GSK
GSK plc is a biopharma company. The Company’s segments include Commercial Operations and Research and Development. Its portfolio and pipeline are focused on developing medicines and vaccines in four core therapeutic areas, which are the areas of human health it focuses on to prevent and treat disease: respiratory, immunology and inflammation; oncology; human immunodeficiency virus (HIV), and infectious diseases. Its specialty medicines prevent and treat diseases, from HIV to respiratory diseases, immune-mediated conditions like lupus, and cancer. General medicines include inhaled medicines for asthma and COPD with antibiotics. Its portfolio also includes Efimosfermin, a fibroblast growth factor 21 (FGF21) analog therapeutic in clinical development. The Company also engaged in ozureprubart, a long-acting anti-immunoglobulin E (IgE) monoclonal antibody. It is in phase IIb clinical development for prophylactic protection against food allergens.
About the author
Emily J. Thompson
Emily J. Thompson, a Chartered Financial Analyst (CFA) with 12 years in investment research, graduated with honors from the Wharton School. Specializing in industrial and technology stocks, she provides in-depth analysis for Intellectia’s earnings and market brief reports.
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- Vaccine Coverage Potential: With over 40% of U.S. adults aged 60 and older having received a protein-based RSV vaccine, Clover's findings underscore the potential of its RSV+hMPV±PIV3 combination vaccine candidates to restore waning RSV protection and broaden coverage against related respiratory viruses.
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See More
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- Clinical Trial Challenges: In 2023, Pfizer and Valneva dropped about half of the participants due to quality concerns with a third-party clinical trial operator, reducing the trial size from approximately 18,000 to 9,400, which may impact the final efficacy assessment of the vaccine.
- Vaccine Policy Risks: Advancing a vaccine that technically failed a clinical trial under a stricter regulatory environment may pose risks for Pfizer and could serve as a litmus test for vaccine policy in the U.S.
See More
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- Vaccine Development Progress: Pfizer plans to seek regulatory approval for its Lyme disease vaccine despite failing to meet statistical goals in late-stage trials; however, the company claims the vaccine reduced infection rates by over 70% among recipients, indicating strong efficacy.
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- Clinical Trial Challenges: In 2023, Pfizer and Valneva dropped about half of the participants in their Phase 3 trial due to quality concerns with a third-party clinical trial site operator, reducing enrollment from 18,000 to approximately 9,400, highlighting uncertainties in the vaccine development process.
- Vaccine Policy Risks: Advancing a vaccine that technically failed a clinical trial under an administration advocating stricter scrutiny may pose risks for Pfizer, potentially serving as a litmus test for vaccine policy in the U.S. and influencing future approvals and market acceptance.
See More
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Date of Agreement: The agreement was finalized on March 18, 2026, indicating a future-oriented resolution.
See More
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- FDA Approval: GSK announced that its drug Lynavoy has received FDA approval for treating cholestatic pruritus associated with primary biliary cholangitis (PBC), marking the first approved treatment for this condition in the U.S., which is expected to significantly enhance patient quality of life.
- Successful Clinical Trials: The approval is supported by data from the GLISTEN Phase 3 trial, which demonstrated that Lynavoy led to a sustained reduction in cholestatic pruritus and itch-related sleep disturbances over 24 weeks, confirming its efficacy and safety in treatment.
- Global Collaboration Agreement: GSK has signed an agreement with Italian pharma company Alfasigma to manufacture and market Lynavoy globally, which will help accelerate the drug's market introduction and expand its market reach.
- Commitment to R&D: GSK's R&D head, Kaivan Khavandi, stated that Lynavoy is the first liver medicine from their pipeline to receive approval, underscoring the company's ongoing commitment to innovation in liver disease, with potential for further drug development in this area.
See More
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- Vaccination Guidelines Blocked: A Massachusetts federal judge, Brian Murphy, issued a preliminary injunction against the HHS's plan to reduce the number of diseases covered by routine vaccinations from 17 to 11 under Secretary Robert F. Kennedy Jr., safeguarding children's health from potential risks.
- New Appointments Stayed: The judge also stayed the appointments of 13 new Advisory Committee on Immunization Practices members scheduled for June and September 2025 and January this year, indicating a strong emphasis on procedural compliance in public health governance.
- Critique of Procedural Failures: Judge Murphy criticized the Trump administration for bypassing the ACIP to alter immunization schedules, highlighting this technical procedural failure as a serious disregard for the committee's expertise, which raises concerns about the legality of the newly appointed ACIP members.
- Importance of Scientific Decision-Making: American Public Health Association CEO Georges Benjamin emphasized that the injunction underscores the necessity of employing science and qualified experts in public health decision-making, advocating for a transparent process to rebuild public trust and ensure the effectiveness of health interventions.
See More
