Recent 8-K filings for OSTX

• April 30, 2026, 7:59 PM ET regulatory materiality 0.85 positive item 7.01item 9.01

  EMA rolling review for OST-HER2; ATGA aligns on 3-year OS endpoint; peak EU sales >$300M

  EMA initiated rolling review of OST-HER2 CMA for preventing recurrence in resected pulmonary metastatic osteosarcoma.

• April 2, 2026, 7:59 PM ET other material materiality 0.70 neutral item 1.01item 8.01item 9.01 ◈ Material Agreements

  OS Therapies completes $5.25M registered direct offering, expects $4M non-dilutive funds from UK subsidiary

  Gross proceeds $5.25M; net proceeds ~$4.7M from offering of 2.5M shares (or pre-funded warrants) and 3.8M common warrants at $1.40/share.

• March 31, 2026, 7:59 PM ET other materiality 0.20 neutral item 8.01item 9.01

  OS Therapies files prospectus supplement for resale of up to 10.5M shares by selling stockholders

  Filed prospectus supplement covering resale of up to 10,529,417 shares of common stock by selling stockholders.

• March 6, 2026, 6:59 PM ET debt materiality 0.65 negative item 1.01item 2.03item 3.02item 9.01 ◈ Debt Financings◈ Material Agreements

  OS Therapies raises $2M via 10% OID convertible notes and warrants; $2.2M principal

  Gross proceeds $2M; notes carry 4% interest, mature March 4, 2027.

• February 13, 2026, 6:59 PM ET other material materiality 0.30 neutral item 8.01

  OS Therapies extends warrant exercise inducement period to March 2, 2026

  Company extended offering period for warrant inducement from Feb 10 to March 2, 2026.

• January 12, 2026, 6:59 PM ET other material materiality 0.70 positive item 1.01item 3.02item 8.01item 9.01 ◈ Material Agreements

  OS Therapies raises $7.53M via warrant exercise inducement from all 9 existing holders

  Gross proceeds of $7.53M from exercise or pre-funding of 5,382,148 Existing Warrants at $1.40/share.

• October 21, 2025, 7:59 PM ET other material materiality 0.60 neutral item 5.02item 5.07item 9.01

  OSTX shareholders approve 200M share increase, Ayala issuance, and plan amendment at annual meeting

  Charter amendment to increase authorized shares from 50M to 150M approved with 12.6M For, 228K Against, 16.3K Abstain.

• October 17, 2025, 7:59 PM ET other material materiality 0.20 neutral item 7.01item 8.01item 9.01

  OS Therapies adjourns 2025 annual meeting to Oct 21; posts investor presentation

  Annual meeting adjourned on Oct 14; reconvenes virtually Oct 21 at 10:00 a.m. ET to allow more proxy solicitation time.

• September 30, 2025, 7:59 PM ET other material materiality 0.50 neutral item 8.01item 9.01

  OS Therapies files prospectus supplement for resale of up to 4.37M shares by selling stockholders

  Prospectus supplement covers resale of up to 4,373,043 shares of common stock by selling stockholders.

• September 2, 2025, 7:59 PM ET other material materiality 0.65 neutral item 1.01item 3.02item 8.01item 9.01

  OS Therapies completes warrant inducement, raises $3.8M; extends funding into 2027

  Raised ~$3.78M gross from exercise of 3,373,043 existing warrants at $1.12; issued new warrants at $3.00 exercise price.

• August 26, 2025, 7:59 PM ET other material materiality 0.60 positive item 1.02item 8.01item 9.01

  OS Therapies terminates $15M equity line; $4.2M raised, burn reduced

  Terminated ELOC Purchase Agreement with Square Gate effective Aug 26, 2025; no outstanding borrowings or fees.

• August 19, 2025, 7:59 PM ET earnings materiality 0.80 positive item 2.02item 9.01

  OS Therapies Q2 net loss $4.5M; FDA confirms RMAT, issues BLA number for OST-HER2, Phase 2b data positive

  FDA confirmed OST-HER2 meets biological criteria for RMAT; issued BLA number for Accelerated Approval submission.

• August 15, 2025, 7:59 PM ET other material materiality 0.25 neutral item 5.03item 9.01 ◈ Governance Changes

  OS Therapies amends bylaws to reduce stockholder meeting quorum to one-third of voting power

  Board approved amendment to Section 3.10 of Article III of the Bylaws on August 15, 2025.

• July 14, 2025, 7:59 PM ET other material materiality 0.75 positive item 1.01item 3.02item 8.01item 9.01

  OS Therapies closes $4.2M warrant exercise inducement; extends cash runway to 2026

  Raised $4.2M gross from exercise of 3.8M existing warrants at $1.12/share; issued new warrants at $3.00/share.

• June 27, 2025, 7:59 PM ET other material materiality 0.50 neutral item 1.01item 3.02

  OS Therapies completes second closing of warrant inducement; raises ~$616K

  Second closing: holders exercised Existing Warrants for 550,004 shares at $1.12; issued New Warrants for 550,004 shares at $3.00, 5-year term.

• June 24, 2025, 7:59 PM ET other material materiality 0.60 positive item 1.01item 3.02item 8.01item 9.01

  OS Therapies (OSTX) raises up to $8M via warrant exercise inducement; extends cash runway into H2 2026

  Holders exercise 1.57M old warrants ($1.12) for cash; receive new 5-year warrants at $3.00/sh.

• May 16, 2025, 7:59 PM ET earnings materiality 0.75 neutral item 2.02item 9.01

  OS Therapies Q1 net op loss $3.876M; OST-HER2 BLA on track for Q3 2025

  Net operating loss of $3.876M in Q1 2025 vs $1.490M in Q1 2024, due to trial closeout and regulatory prep costs.

• April 15, 2025, 7:59 PM ET M&A materiality 0.85 positive item 2.01item 3.02item 1.01item 8.01item 9.01

  OS Therapies closes $8M asset acquisition from Ayala; eliminates $20M milestones, cuts royalty to 1.5%

  Total consideration $8M: $400k cash to Ayala, $100k to third party, $7.5M in stock (4,774,637 shares at VWAP).

• April 9, 2025, 7:59 PM ET other material materiality 0.15 neutral item 5.07item 9.01

  Stockholders approve issuance of shares exceeding 20% of outstanding common stock

  Special meeting held April 9, 2025; proposal passed with 11,587,018 votes in favor (99.3% of votes cast).

• April 2, 2025, 7:59 PM ET other material materiality 0.20 neutral item 8.01item 9.01

  OS Therapies adjourns Special Meeting due to lack of quorum; reconvenes April 9, 2025

  Special Meeting on March 31, 2025 lacked quorum; no business was conducted.

• March 31, 2025, 7:59 PM ET earnings materiality 0.60 negative item 2.02item 9.01

  OS Therapies reports FY2024 net operating loss of $10.9M; cash runway into 2026

  Net operating loss $10.886M in 2024 vs $7.916M in 2023, driven by IPO costs.

• January 29, 2025, 6:59 PM ET M&A materiality 0.75 positive item 1.01item 3.02item 5.02item 8.01item 9.01 ◈ executive_change

  OS Therapies acquires Ayala's listeria IP for $8M, eliminates milestones, adds Phase 2 lung asset

  Total consideration $8M: $0.5M cash + $7.5M in OSTX shares; 180-day lock-up. Closes ~60 days.

• January 15, 2025, 6:59 PM ET other material materiality 0.60 neutral item 8.01item 9.01

  OS Therapies completes private placement raising ~$7.1M in gross proceeds

  Aggregate gross proceeds from first and second closings total approximately $7,103,000.

• January 14, 2025, 6:59 PM ET other material materiality 0.70 neutral item 1.01item 3.02item 9.01

  OS Therapies completes second closing of $1.05M private placement

  Second closing sold 263,250 units at $4.00 each, raising $1.053 million in gross proceeds.

• January 3, 2025, 6:59 PM ET other material materiality 0.75 positive item 1.01item 3.02item 8.01item 9.01

  OS Therapies closes $6M private placement; funds operations into 2026

  Raised $6.05M gross from sale of 1,512,500 units at $4.00/unit; each unit has Series A Convertible Preferred share and a warrant.

• December 30, 2024, 6:59 PM ET other material materiality 0.75 positive item 1.01item 3.02item 5.03item 8.01item 9.01

  OS Therapies announces $6M private placement; OST-HER2 Phase 2b data in Jan 2025

  Gross proceeds of $6M from sale of 1.5M units at $4.00/unit; each unit = 1 share Series A convertible preferred + 1 warrant.

• November 15, 2024, 6:59 PM ET earnings materiality 0.75 neutral item 2.02item 9.01

  OS Therapies Q3 net loss $2.9M; Phase 2b osteosarcoma data due Dec 2024

  Net operating loss $2.875M in Q3 2024 vs $2.006M in Q3 2023; EPS -$0.18 vs -$0.38.

• November 1, 2024, 7:59 PM ET other material materiality 0.75 neutral item 1.01item 3.02item 9.01

  OS Therapies secures up to $15M equity line from Square Gate Capital over 24 months

  Company can sell up to $15M of common stock to Square Gate at 95% of lowest VWAP during valuation period.

• October 28, 2024, 7:59 PM ET leadership materiality 0.55 positive item 5.02item 9.01 ◈ executive_change ×4

  OS Therapies appoints two new independent directors; Chairman Goddard and Joacim Borg resign

  Colin Goddard (Chairman) and Joacim Borg resigned effective Oct 28, 2024; no disagreement with company operations.

• August 22, 2024, 7:59 PM ET other material materiality 0.05 neutral item 8.01item 9.01

  OS Therapies clarifies CUSIP change for common stock from 68764Y108 to 68764Y207

  New CUSIP 68764Y207 assigned effective August 5, 2024, replacing old CUSIP 68764Y108.

• August 15, 2024, 7:59 PM ET earnings materiality 0.80 positive item 2.02item 9.01

  OS Therapies reports Q2 2024 net operating loss of $1.557M; IPO raises $6.4M post-quarter

  Q2 2024 net operating loss $1.557M vs $2.505M in Q2 2023; EPS loss $0.26 on 5.991M shares.

Executive changes

Earnings & guidance

Materiality & sentiment trend

Max materiality 0.85 · Median 0.65 · Most common event other_material

12 positive 2 negative 17 neutral

source · OSTX on sec.gov