CTLA4 cytotoxic T-lymphocyte associated protein 4
ENSG00000163599 · protein coding · Open Targets profile
Inhibitory receptor acting as a major negative regulator of T-cell responses (PubMed:11279501, PubMed:11279502, PubMed:16551244, PubMed:1714933, PubMed:18641304, PubMed:28484017). Acts as a decoy receptor: the affinity of CTLA4 for its natural B7 family ligands, CD80 and CD86, is considerably stronger than the affinity of their cognate stimulatory coreceptor CD28 (PubMed:11279501, PubMed:11279502, PubMed:16551244, PubMed:1714933, PubMed:28484017). {ECO:0000269|PubMed:11279501, ECO:0000269|PubMed:11279502, ECO:0000269|PubMed:1714933, ECO:0000269|PubMed:18641304, ECO:0000269|PubMed:28484017, ECO:0000303|PubMed:16551244}.
Each band is a group of drugs. It runs from the kind of drug on the left to the furthest stage that drug has reached in any disease on the right. Thicker bands mean more drugs.
Approved bands are highlighted. Withdrawn means the drug was pulled from the market or from development. A combined phase counts as the later one (Phase 1/2 is shown as Phase 2). Hover a band for the drug names. Source: Open Targets Platform, fetched live.
Each row is a cancer, strongest overall evidence first. The two dots show how strong the inherited (germline) and tumour-mutation (somatic) evidence is; the line between them is the gap.
Scores run from 0 (no evidence) to 1 (strongest). A missing dot at 0 means Open Targets holds no evidence of that kind. Source: Open Targets Platform, fetched live.
Tractability
- Small molecule
- Structure with Ligand
- Antibody
- Approved Drug, UniProt loc high conf, GO CC high conf, UniProt SigP or TMHMM
gnomAD loss of function constraint: o/e 0.14740000665187836 (upper bound 0.380950003862381). Low values mean loss of function is poorly tolerated, a safety flag for inhibition.
Who runs trials of these drugs
Principal investigators and study chairs on 400 registry trials, updated in the last three years, of the most advanced drugs against CTLA4 (ipilimumab, quavonlimab, cadonilimab, erfonrilimab, zalifrelimab), ranked by Phase 2+ trials. Live from ClinicalTrials.gov.
- Ahmad TarhiniECOG-ACRIN Cancer Research Group · 4 of 4 trials Phase 2+
- Frank S HodiECOG-ACRIN Cancer Research Group · 3 of 3 trials Phase 2+
- Zeynep ErogluMoffitt Cancer Center · 3 of 3 trials Phase 2+
- Eric JonaschM.D. Anderson Cancer Center · 2 of 3 trials Phase 2+
- Evan J LipsonJHU Sidney Kimmel Comprehensive Cancer Center LAO · 2 of 3 trials Phase 2+Ph1NCT03816332 · Tacrolimus, Nivolumab, and Ipilimumab in Treating Kidney Transplant Recipients With Selected Unresectable or Metastatic Cancersbrief
- David HsiehUniversity of Texas Southwestern Medical Center · 2 of 2 trials Phase 2+
- Geoffrey T GibneyECOG-ACRIN Cancer Research Group · 2 of 2 trials Phase 2+
- Georgina LongMelanoma Institute Australia · 2 of 2 trials Phase 2+
- Janice MehnertNYU Langone Health · 2 of 2 trials Phase 2+
- Jiafu JiPeking University Cancer Hospital & Institute · 2 of 2 trials Phase 2+
- Katherine BeverSKCCC Johns Hopkins Medical Institution · 2 of 2 trials Phase 2+
- Michael B AtkinsECOG-ACRIN Cancer Research Group · 2 of 2 trials Phase 2+
- Michael PostowMemorial Sloan Kettering Cancer Center · 2 of 2 trials Phase 2+
- Patrick FordeJohns Hopkins University · 2 of 2 trials Phase 2+
- A P ChenNational Cancer Institute LAO · 1 of 2 trials Phase 2+
Registry trials of ipilimumab, quavonlimab, cadonilimab, erfonrilimab, zalifrelimab updated in the last three years, counted by the country group of their listed sites. A trial with sites in several groups counts in each; 299 of 386 have all sites in one country.
Site counts are not patients per country, and trials registered only outside ClinicalTrials.gov are not covered. Where sites are is a fact about the record, not a judgement of its quality. Europe is the EU and EEA, the UK and Switzerland. 14 trials list no sites and are left out. Source: ClinicalTrials.gov, fetched live.
179 trials of drugs against CTLA4 were stopped early; 8 give no reason
Terminated, withdrawn and suspended interventional trials of ipilimumab, quavonlimab, cadonilimab, erfonrilimab, zalifrelimab, newest update first, live from ClinicalTrials.gov. Each reason is quoted exactly as the registry gives it; we do not sort reasons into safety, efficacy or business. Dates are the last registry update. Showing the 25 most recent of 179.
- suspended · 2026-11-02 · National Cancer Institute (NCI) · Ipilimumab“End of Initial Phase of Multi-phase protocol”
- suspended · 2026-11-02 · National Cancer Institute (NCI) · Ipilimumab“Scheduled Interim Monitoring”
- terminated · 2026-10-20 · M.D. Anderson Cancer Center · Ipilimumab“The study met its prespecified futility criteria during the prespecified interim futility analysis after enrolling the first cohort of 10 patients.”
- suspended · 2026-10-19 · National Cancer Institute (NCI) · matched by the registry's drug synonyms“On hold pending planned interim analysis.”
- withdrawn · 2026-10-19 · University of Utah · Ipilimumab“Low Accrual”
- suspended · 2026-10-08 · City of Hope Medical Center · Ipilimumab“09/29/2026 DSMC: Opened in order to apply suspension.”
- terminated · 2026-09-28 · Akeso · matched by the registry's drug synonyms“Sponsor decision”
- terminated · 2026-09-23 · Hackensack Meridian Health · Ipilimumab“Slow Accrual”
- suspended · 2026-09-04 · Washington University School of Medicine · Ipilimumab“Protocol amendment”
- suspended · 2026-08-17 · National Cancer Institute (NCI) · Ipilimumab“Other - Pending amendment.”
- terminated · 2026-08-04 · Academic and Community Cancer Research United · Ipilimumab“Sponsor has withdrawn support for the study.”
- terminated · 2026-07-16 · Dana-Farber Cancer Institute · Ipilimumab“Slow accrual, competing studies, and lack of efficacy”
- withdrawn · 2026-06-10 · National Cancer Institute (NCI) · Ipilimumab“Inadequate accrual rate”
- terminated · 2026-06-03 · University of Wisconsin, Madison · Ipilimumab“Administrative”
- terminated · 2026-05-26 · ImmunityBio, Inc. · NAI + Nivolumab + Ipilimumab, Nogapendekin alfa inbakicept (NAI) + Nivolumab + Ipilimumab + Carboplatin + Nab-paclitaxel“There are no longer active subjects on QUILT-2.023. Data will be entered into clinicaltrials.gov within 1 year of the primary completion date.”
- terminated · 2026-05-15 · Iovance Biotherapeutics, Inc. · Ipilimumab“After reviewing the available safety and efficacy data to date, Iovance concluded that the study reached the required number of events for evaluation of study endpoints.”
- terminated · 2026-05-05 · Eziafa Oduah, MD, PhD, MPH · Ipilimumab“Slow enrollment.”
- terminated · 2026-04-30 · M.D. Anderson Cancer Center · Ipilimumab“<75% participation”
- terminated · 2026-04-23 · Emory University · Ipilimumab“Slow accrual”
- terminated · 2026-04-21 · Incyte Corporation · ipilimumab“Further development of this compound with ipilimumab in the treatment of melanoma is no longer being pursued.”
- terminated · 2026-04-20 · Servier Bio-Innovation LLC · Ipilimumab“The sponsor decided to terminate the study during the safety lead-in phase.”
- terminated · 2026-04-07 · M.D. Anderson Cancer Center · Ipilimumab“<75% participation”
- terminated · 2026-04-03 · Hackensack Meridian Health · Ipilimumab“Lack of Accrual”
- terminated · 2026-03-13 · University Hospital, Essen · Ipilimumab“The clinical trial has been terminated due to the revocation of funding. Although one subject was enrolled, the participant withdrew prior to receiving any treatment. No trial-related procedures generating evaluable clinical data were performed.”
- terminated · 2026-03-09 · Pfizer · ipilimumab“Study terminated due to inability to recruit the target number of patients. There were no safety and/or efficacy concerns involved in the decision to stop enrollment.”
Paediatric incentives and obligations for CTLA4's drugs
For ipilimumab, quavonlimab, cadonilimab, erfonrilimab, zalifrelimab: what EMA and FDA publish about paediatric plans, orphan status and pediatric approvals, and how many registered studies take children. Each line is a yes, no or not published fact from the record linked under it; none of it is a forecast.
- FDA pediatric target list: yes · CTLA4 is on the list. Membership alone neither requires nor waives a pediatric study.Rule: Target is on FDA's Pediatric Molecular Target List (relevant targets). Source: FDA Pediatric Molecular Target List (Listed as February 2026 on the FDA Pediatric Oncology page; the file served is 9.7.22_the_relevant_molecular_target_list.xlsx, whose Summary of Changes sheet is headed 'SEPTEMBER 2022 UPDATE' (footnote date 2022-09-01)), 2026-11-11
- EU paediatric investigation plan: yes · EMEA-002949-PIP01-20 (quavonlimab;pembrolizumab, Treatment of all conditions included in the category of malignant neoplasms (except nervous system, haematopoietic and lymphoid tissue neoplasms and melanoma);Treatment of malignant neoplasms of the central nervous system): W: decision granting a waiver in all age groups for all conditions or indications, 10 May 2021; EMEA-000117-PIP02-10-M07 (Ipilimumab, Treatment of melanoma): PM: decision on the application for modification of an agreed PIP, 12 Jan 2017; compliance positive 24 Feb 2017; EMEA-000117-PIP01-07-M07 (Ipilimumab, Treatment of all conditions included in the category of malignant neoplasms (except melanoma, nervous system, haematopoietic and lymphoid tissue)): PM: decision on the application for modification of an agreed PIP, 8 May 2015; compliance positive 11 Dec 2015Rule: An EMA PIP decision (agreement, modification or waiver) lists the drug as its active substance, exact name. Source: EMA data download (dated snapshot), 2026-11-11
- EU orphan designation: no · No EU orphan designation names ipilimumab, quavonlimab, cadonilimab, erfonrilimab, zalifrelimabRule: An EU orphan designation lists the drug as its active substance (exact name) or belongs to a medicine that does; withdrawn and expired designations are listed with their status. Source: EMA data download (dated snapshot), 2026-11-11
- Authorised in the EU: yes · Yervoy: authorised since 13 Jul 2011Rule: An EMA medicine record lists the drug as its active substance or INN, exact name; national-only authorisations are not in this file. Source: EMA EPAR Yervoy, 2026-11-11
- FDA orphan designation: not published · FDA's orphan designation database turns away automated requests, so this app does not read it; search it by hand at the linkRule: Would be: an FDA orphan designation names the drug. Source: FDA orphan designations search
- FDA pediatric oncology approval: yes · Ipilimumab [Yervoy], 8 Apr 2025: In combination with nivolumab, for the treatment of adult and pediatric patients 12 years and older with unresectable or metastatic microsatellite instability high (MSI-H) or mismatch repair deficient (dMMR) colorectal cancer (CRC); Ipilimumab [Yervoy], 15 Feb 2023: As a single agent or in combination with nivolumab, for the treatment of unresectable or metastatic melanoma in adult and pediatric patients 12 years and olderRule: FDA's Pediatric Oncology Drug Approvals table names the drug. Source: FDA Pediatric Oncology Drug Approvals (content current as of 2026-03-03), 2026-11-11
- Registered studies open to children: yes · 55 interventional studies of ipilimumab, quavonlimab, cadonilimab, erfonrilimab, zalifrelimab include patients under 18; 20 are recruiting, not yet recruiting or activeRule: The registry's age group includes Child (birth to 17 years), which also counts studies that set no minimum age. Source: ClinicalTrials.gov search, 2026-11-11
Rare pediatric disease voucher. FDA, content current as of 29 Apr 2026: “As of February 3, 2026, enactment of the Consolidated Appropriations Act, 2026, the rare pediatric disease PRV program will sunset after September 30, 2029. FDA may not award any PRVs under this program after September 30, 2029.” Voucher sale prices are not shown here; they appear only as company-reported news. FDA: Rare Pediatric Disease Designation and Priority Review Voucher Programs
All 6 drugs and clinical candidates as a table
Each drug, stage and indication links to its Open Targets record, where the trials and approvals behind it are listed. Salt forms (for example a mesylate) are listed as Open Targets records them, as separate entries.