LTB4R2 leukotriene B4 receptor 2
ENSG00000213906 · protein coding · Open Targets profile
Low-affinity receptor for leukotrienes including leukotriene B4. Mediates chemotaxis of granulocytes and macrophages. The response is mediated via G proteins that activate a phosphatidylinositol-calcium second messenger system. The rank order of affinities for the leukotrienes is LTB4 > 12-epi-LTB4 > LTB5 > LTB3.
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 Withdrawn means the drug was pulled from the market or from development.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
- Advanced Clinical, High-Quality Ligand, Druggable Family
- Antibody
- GO CC high conf, UniProt loc med conf, UniProt SigP or TMHMM, Human Protein Atlas loc
- PROTAC
- Small Molecule Binder
- Other modalities
- Advanced Clinical
gnomAD loss of function constraint: o/e 1.136199951171875 (upper bound 2.242500066757202). 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 4 registry trials, updated in the last three years, of the most advanced drugs against LTB4R2 (nomacopan, CP-195543), ranked by Phase 2+ trials. Live from ClinicalTrials.gov.
- Sajjad AhmadMoorfields Eye Hospital NHS Foundation Trust · 1 of 1 trials Phase 2+
- Wynne Weston DaviesAKARI Therapeutics · 1 of 1 trials Phase 2+
Registry trials of nomacopan, CP-195543 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; 1 of 4 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. Source: ClinicalTrials.gov, fetched live.
5 trials of drugs against LTB4R2 were stopped early
Terminated, withdrawn and suspended interventional trials of nomacopan, CP-195543, 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 5 most recent of 5.
- terminated · 2025-06-05 · AKARI Therapeutics · nomacopan (rVA576)“The early termination of this study is a business decision following a portfolio reprioritization plan. The decision is not related to any Efficacy, Safety or Clinical concerns regarding Nomacopan/rVA576”
- terminated · 2025-04-10 · AKARI Therapeutics · matched by the registry's drug synonyms“The early termination of this study is a business decision, Akari have made the decision to close their global Phase III PNH program. The decision was not related to any efficacy, safety or clinical concerns regarding Coversin/rVA576.”
- terminated · 2025-04-10 · AKARI Therapeutics · matched by the registry's drug synonyms“The trial has terminated early due to the disruptions caused by the ongoing COVID-19 pandemic. The decision was not related to any efficacy, safety or clinical concerns regarding rVA576.”
- withdrawn · 2025-04-09 · AKARI Therapeutics · nomacopan (rVA576)“Akari has decided to discontinue AK802 study due to strategic resource allocation decisions.”
- terminated · 2014-09-25 · Pfizer · matched by the registry's drug synonyms“See Detailed Description field”
Paediatric incentives and obligations for LTB4R2's drugs
For nomacopan, CP-195543: 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: no · LTB4R2 is not on the listRule: 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: no · No EMA paediatric investigation plan decision names nomacopan, cp-195543Rule: 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: yes · EU/3/23/2810 positive 25 Jul 2023: Treatment in haematopoietic stem cell transplantation; EU/3/20/2289 positive 26 Jun 2020: Treatment of bullous pemphigoid; EU/3/16/1725 positive 29 Aug 2016: Treatment of paroxysmal nocturnal haemoglobinuria; EU/3/16/1687 positive 27 Jun 2016: Treatment of Guillain-Barré syndromeRule: 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: no · EMA lists no centrally authorised medicine of nomacopan, cp-195543Rule: 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 data download (dated snapshot), 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: no · FDA's table lists no pediatric approval of nomacopan, cp-195543Rule: FDA's Pediatric Oncology Drug Approvals table names the drug. Source: FDA Pediatric Oncology Drug Approvals (content current as of 2026-03-03), 2026-11-12
- Registered studies open to children: yes · 1 interventional studies of nomacopan, cp-195543 include patients under 18; 0 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, 2026-11-12
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 2 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.
| Drug | Type | Highest stage | Indications | Source records |
|---|---|---|---|---|
| NOMACOPAN | Unknown | phase 3 | bullous pemphigoid, thrombotic microangiopathy, paroxysmal nocturnal hemoglobinuria, atopic conjunctivitis, type 1 diabetes mellitus | Open Targets · ChEMBL |
| CP-195543 | Small molecule | phase 2 | rheumatoid arthritis | Open Targets · ChEMBL |