{"filing":{"accession_number":"0001628280-26-063497","cik":"0001662579","ticker":"CCCC","company_name":"C4 Therapeutics, Inc.","form":"8-K","filing_date":"2026-09-25","report_date":"2026-09-25","primary_document":"cccc-20260925.htm","primary_document_url":"https://www.sec.gov/Archives/edgar/data/1662579/000162828026063497/cccc-20260925.htm"},"events":[{"id":35009,"run_id":32239,"accession_number":"0001628280-26-063497","anchor_item_number":"8.01","event_type":"operational_other","event_domain":"operational","is_material":true,"confidence":0.75,"summary":"C4 Therapeutics disclosed presentation of new biomarker data from Phase 1 and Phase 1b clinical trials of cemsidomide at the 23rd International Myeloma Society Annual Meeting, demonstrating positive immunomodulatory findings and safety clearance of the 75 µg dose level. The Phase 1b trial has advanced to dose escalation and expansion cohorts, with additional data expected in mid-2027.","company_name":"C4 Therapeutics, Inc.","ticker":"CCCC","filing_date":"2026-09-25","form":"8-K","submitted_at":null,"items":[{"id":38924,"accession_number":"0001628280-26-063497","item_number":"7.01","item_title":"Regulation FD Disclosure.","event_type":"operational_other","event_domain":"operational","is_material":true,"confidence":0.75,"reasoning":"C4 Therapeutics disclosed presentation of new biomarker data from Phase 1 and Phase 1b clinical trials of cemsidomide at a medical conference (23rd IMS Annual Meeting), along with advancement of the Phase 1b trial to dose escalation and expansion cohorts. This is a clinical development milestone and operational update regarding the company's lead oncology program, not a financial result, executive change, M\u0026A activity, or other specifically-named event type. The disclosure is material as it provides substantive clinical progress on the company's primary therapeutic candidate and informs investors of trial advancement and safety clearance.","classifier_version":"claude-haiku-4-5-20251001+prompt-a85dd512","taxonomy_version":"v1.3","classified_at":"2026-09-25T11:06:06.038151+00:00","company_name":"","ticker":null,"filing_date":""},{"id":38925,"accession_number":"0001628280-26-063497","item_number":"8.01","item_title":"Other Events.","event_type":"operational_other","event_domain":"operational","is_material":true,"confidence":0.75,"reasoning":"C4 Therapeutics announced new biomarker data from Phase 1 and Phase 1b clinical trials of cemsidomide in combination with dexamethasone and elranatamab, presented at the 23rd International Myeloma Society Annual Meeting. The disclosure highlights positive immunomodulatory biomarker findings, safety clearance of the 75 µg dose level, and advancement to dose escalation and expansion cohorts with data expected in mid-2027. This is a material clinical development milestone for a clinical-stage biopharmaceutical company's lead program, affecting investor assessment of pipeline progress and value inflection points, but does not fit the specific categories of earnings release, M\u0026A, restatement, or other defined event types—making it an operational/strategic business event.","classifier_version":"claude-haiku-4-5-20251001+prompt-a85dd512","taxonomy_version":"v1.3","classified_at":"2026-09-25T11:06:06.038151+00:00","company_name":"","ticker":null,"filing_date":""}]}],"classifications":[{"id":38924,"accession_number":"0001628280-26-063497","item_number":"7.01","item_title":"Regulation FD Disclosure.","event_type":"operational_other","event_domain":"operational","is_material":true,"confidence":0.75,"reasoning":"C4 Therapeutics disclosed presentation of new biomarker data from Phase 1 and Phase 1b clinical trials of cemsidomide at a medical conference (23rd IMS Annual Meeting), along with advancement of the Phase 1b trial to dose escalation and expansion cohorts. This is a clinical development milestone and operational update regarding the company's lead oncology program, not a financial result, executive change, M\u0026A activity, or other specifically-named event type. 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The disclosure highlights positive immunomodulatory biomarker findings, safety clearance of the 75 µg dose level, and advancement to dose escalation and expansion cohorts with data expected in mid-2027. This is a material clinical development milestone for a clinical-stage biopharmaceutical company's lead program, affecting investor assessment of pipeline progress and value inflection points, but does not fit the specific categories of earnings release, M\u0026A, restatement, or other defined event types—making it an operational/strategic business event.","classifier_version":"claude-haiku-4-5-20251001+prompt-a85dd512","taxonomy_version":"v1.3","classified_at":"2026-09-25T11:06:06.038151+00:00","company_name":"C4 Therapeutics, Inc.","ticker":"CCCC","filing_date":"2026-09-25"}]}