IMPA1 inositol monophosphatase 1
ENSG00000133731 · protein coding · Open Targets profile
Phosphatase involved in the dephosphorylation of myo-inositol monophosphates to generate myo-inositol (PubMed:17068342, PubMed:8718889, PubMed:9462881). Is also able to dephosphorylate scyllo-inositol-phosphate, myo-inositol 1,4-diphosphate, scyllo- inositol-1,3-diphosphate and scyllo-inositol-1,4-diphosphate (PubMed:17068342). Also dephosphorylates in vitro other sugar- phosphates including D-galactose-1-phosphate, glucose-1-phosphate, glucose-6-phosphate, fructose-1-phosphate, beta-glycerophosphate and 2'-AMP (PubMed:17068342, PubMed:8718889, PubMed:9462881). Responsible for the provision of inositol required for synthesis of phosphatidylinositols and polyphosphoinositides, and involved in maintaining normal brain function (PubMed:26416544, PubMed:8718889). Has been implicated as the pharmacological target for lithium (Li(+)) action in brain, which is used to treat bipolar affective disorder (PubMed:17068342). Is equally active with 1D-myo-inositol 1-phosphate, 1D-myo-inositol 3-phosphate and D-galactose 1-phosphate (PubMed:9462881). {ECO:0000269|PubMed:17068342, ECO:0000269|PubMed:26416544, ECO:0000269|PubMed:8718889, ECO:0000269|PubMed:9462881}.
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 Withdrawn means the drug was pulled from the market or from development.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
- Approved Drug, Structure with Ligand, High-Quality Pocket, Druggable Family
- PROTAC
- Database Ubiquitination, Half-life Data
gnomAD loss of function constraint: o/e 0.6013299822807312 (upper bound 0.8659300208091736). 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 129 registry trials, updated in the last three years, of the most advanced drugs against IMPA1 (lithium, lithium carbonate), ranked by Phase 2+ trials. Live from ClinicalTrials.gov.
- Thomas GuttusoUniversity at Buffalo · 2 of 2 trials Phase 2+
- Polyxeni GeorgilaPrivate Practice · 1 of 2 trials Phase 2+
- Aglaia VignoliUniversity of Milan · 1 of 1 trials Phase 2+
- Aristotle VoineskosCentre for Addiction and Mental Health · 1 of 1 trials Phase 2+
- Barry F ChaitinUniversity of California, Irvine · 1 of 1 trials Phase 2+
- Christopher MorrowJohns Hopkins University · 1 of 1 trials Phase 2+
- Claire O'DonovanQueen Elizabeth II Health Sciences Centre, CDHA · 1 of 1 trials Phase 2+
- DECHANET AlineAssistance Publique - Hôpitaux de Paris (AP-HP) · 1 of 1 trials Phase 2+
- Delorme RichardAPHP · 1 of 1 trials Phase 2+
- Diane NamSunnybrook Health Sciences Centre · 1 of 1 trials Phase 2+
- DP DevanandColumbia University · 1 of 1 trials Phase 2+
- Edward HueyBrown University · 1 of 1 trials Phase 2+
- Eric LenzeWashington University School of Medicine · 1 of 1 trials Phase 2+
- Eric SicardAlzamend · 1 of 1 trials Phase 2+
- Fouad ChebibMayo Clinic · 1 of 1 trials Phase 2+
Registry trials of lithium, lithium carbonate 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; 111 of 120 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. 9 trials list no sites and are left out. Source: ClinicalTrials.gov, fetched live.
46 trials of drugs against IMPA1 were stopped early; 5 give no reason
Terminated, withdrawn and suspended interventional trials of lithium, lithium carbonate, 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 46.
- terminated · 2026-11-05 · Dr. Inge Winter · Lithium“The site in Israel stopped recruitment due to logistic reasons. Other sites are recruiting for 2023-506602-39-00, 2023-506605-19-00, 2023-506617-21-00.”
- terminated · 2026-05-13 · Stichting TRICALS Foundation · Lithium Carbonate 400 MG“The planned interim analysis showed no survival benefit of taking the drug when compared with placebo.”
- terminated · 2025-10-23 · Ivoclar Vivadent AG · matched by the registry's drug synonyms“Material did not perform accordingly in other clinical trials.”
- terminated · 2025-09-25 · Negovsky Reanimatology Research Institute · Lithium Carbonate“Decision of the local ethics committee”
- terminated · 2025-07-08 · Cancer Trials Ireland · Lithium“Poor accrual and the field has moved on.”
- terminated · 2025-03-25 · University Hospital, Montpellier · matched by the registry's drug synonyms“no more inclusion”
- withdrawn · 2024-09-19 · Nova Scotia Health Authority · Lithium“recruitment difficulties”
- terminated · 2024-07-25 · University of Michigan · matched by the registry's drug synonyms“Loss of funding due to COVID-19”
- terminated · 2024-04-29 · VA Office of Research and Development · Lithium“terminated early due to non-safety related DMC recommendations”
- terminated · 2023-04-13 · University of Michigan · matched by the registry's drug synonyms“COVID, loss of funding”
- withdrawn · 2023-03-01 · Yale University · Ketamine/Lithium“No funding”
- withdrawn · 2021-10-08 · University of British Columbia · matched by the registry's drug synonyms“Unable to recruit participants”
- terminated · 2021-08-12 · University of Michigan · matched by the registry's drug synonyms“COVID shutdown”
- terminated · 2021-01-29 · Nova Scotia Health Authority · lithium“Recruitment difficulties”
- terminated · 2020-07-10 · Keming Gao · Lithium“Lack of funding”
- terminated · 2020-03-25 · Institut Cancerologie de l'Ouest · matched by the registry's drug synonyms“The study stopped due to a death in the arm control”
- terminated · 2020-01-10 · Aziende Chimiche Riunite Angelini Francesco S.p.A · Lithium sulphate prolonged-release 660 mg, Lithium carbonate immediate-release 150 mg and 300 mg“Sponsor's decision due to slow enrollment rate.”
- terminated · 2019-12-09 · University of Wisconsin, Madison · Lithium carbonate“Budget/Funding”
- withdrawn · 2019-04-01 · Smith & Nephew, Inc. · matched by the registry's drug synonyms“Business decision”
- withdrawn · 2018-08-16 · William V. Bobo, M.D. · Lithium“Principal Investigator moved to Jacksonville, FL campus.”
- terminated · 2018-02-28 · Hannover Medical School · LithiumNo reason given
- withdrawn · 2018-02-09 · Ewha Womans University · Lithium“The research project has been cancelled before any participants were enrolled.”
- terminated · 2017-08-16 · University Hospitals Cleveland Medical Center · Lithium“Ran out of funding”
- terminated · 2017-05-09 · Massachusetts General Hospital · matched by the registry's drug synonyms“Lack of enrollment”
- terminated · 2017-04-20 · Massachusetts General Hospital · matched by the registry's drug synonyms“Lack of Enrollment”
Paediatric incentives and obligations for IMPA1's drugs
For lithium, lithium carbonate: 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 · IMPA1 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 lithium, lithium carbonateRule: 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/3/23/2822 positive 16 Aug 2023: Treatment of Kleine Levin syndrome; EU/3/22/2674 positive 10 Aug 2022: Treatment of familial adenomatous polyposis (FAP); EU/3/22/2632 positive 21 Jun 2022: treatment of TBR1-related disorderRule: 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 lithium, lithium carbonateRule: 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 lithium, lithium carbonateRule: 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 · 57 interventional studies of lithium, lithium carbonate include patients under 18; 12 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 |
|---|---|---|---|---|
| LITHIUM CITRATE | Small molecule | approval | bipolar disorder, bipolar I disorder | Open Targets · ChEMBL |
| LITHIUM CARBONATE | Small molecule | phase 4 | bipolar disorder, bipolar I disorder, major depressive disorder, conduct disorder, depressive disorder, bipolar II disorder, alcohol dependence, major depressive episode, +40 more | Open Targets · ChEMBL |