Week of September 12, 2025

The Week at a Glance:

• The Fed’s policy decision remains in focus - Major indices lifted ahead of the September Fed meeting, with investors anticipating a rate cut as inflation concerns subside and the labor market slows

• Finally, a biotech IPO - LB Pharmaceuticals raised $285M to fund late-stage clinical development of its antipsychotic therapy LB-102. The deal marks the first major biotech IPO since February

• The British are not coming - Several major biopharma companies - including Merck/MSD, AstraZeneca, Eli Lilly, and Sanofi - announced in the past week that they are pulling or pausing billions in planned UK investments, citing an uncompetitive policy environment, NHS drug-pricing pressures, and concerns over the UK’s attractiveness for life sciences innovation

• Political economy update - Our investment banking team released an update to Vital Signs – our political economy survey of markets, policy and deal activity. Read the update for the week ending, September 12, 2025.

Markets Overview

• The S&P 500, Nasdaq, and the Dow were up 1.6%, 2.0%, and 1.0%, respectively

  • Major indices posted a strong week as investors looked ahead to the September Fed meeting, where a rate cut is widely expected

Healthcare indices underperformed the broader market as the NYSE Pharma Index was up 0.1%, while the NBI fell 1.6%

Notable changes in share price:

• Rapport Therapeutics (NASDAQ: RAPP): Rapport surged 119% after reporting positive Phase 2a data for its lead asset, RAP-219, in focal onset seizures

• Dianthus Therapeutics (NASDAQ: DNTH): Shares rose 48.6% after Dianthus reported positive Phase 2 results in generalized myasthenia gravis (gMG)

• Maze Therapeutics (NASDAQ: MAZE): Shares rose 45.1% following Phase 1 data for their lead asset MZE782. The results established proof-of-mechanism, showing increased urinary phenylalanine excretion and dose-dependent changes in eGFR, potentially translating to positive effects in PKU and CKD

• Summit Therapeutics (NASDAQ: SMMT): Shares fell 11.8% after longer-term NSCLC data in European and North American patients failed to replicate the PFS benefit observed in Chinese patients, while OS also did not reach statistical significance

Sources: Pitchbook, Biomedtracker, and CapIQ

Equity Markets

IPO Markets:

• LB Pharmaceuticals, Inc.  (NASDAQ: MLYS) completed its IPO, raising $285.0M to support clinical development of antipsychotic therapy LB-102, which will include a Phase 3 trial in acute schizophrenia and Phase 2 trial in bipolar disorder

• No companies filed an S-1 last week

• All 17 companies in the queue intend to raise less than $30.0M in proceeds

• Year-to-date, companies that have gone public in 2025 have had a median gain of 54.7%, while ~70% of companies that have gone public have had accretive share prices

Follow-On Offering Markets:

There were 6 follow-on equity offerings last week totaling $1.3B, including:

• Avidity Biosciences, Inc. (NASDAQ: RNA) raised $600M to advance its antibody–oligonucleotide conjugate (AOC) pipeline, which includes supporting both registrational studies and commercial launches in facioscapulohumeral muscular dystrophy (FSHD), myotonic dystrophy type 1 (DM1), and Duchenne muscular dystrophy (DMD)

• Dianthus Therapeutics, Inc. (NASDAQ: DNTH) raised $251.7M to progress development of claseprubart in generalized myasthenia gravis (Phase 3 ready) and multifocal motor neuropathy (Phase 2 ongoing), as well as fund preclinical R&D

• Rapport Therapeutics, Inc. (NASDAQ: RAPP) raised $250.0M to advance clinical development of RAP-219 in focal onset seizures (Phase 3 ready), bipolar mania (Phase 2 ongoing), and diabetic peripheral neuropathic pain (Phase 2 ready)

• Amylyx Pharmaceuticals, Inc. (NASDAQ: AMLX) raised $175.0M to support commercial readiness and clinical development for Avexitide, a GLP-1 receptor antagonist, for post-bariatric hypoglycemia (Ph3 registrational study ongoing) and congenital hyperinsulinism (Phase 3 ready)

PIPE/RDO Markets:

There were four PIPEs/RDOs last week raising an aggregate $236.5M, including:

• Maze Therapeutics (NASDAQ: MAZE) raised a $150.0M oversubscribed PIPE to advance its pipeline targeting kidney and metabolic diseases. The round included participation from both new and existing investors including Frazier Life Sciences, Deep Track Capital, Driehaus Capital Management, and others

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