SMO smoothened, frizzled class receptor
ENSG00000128602 · protein coding · Open Targets profile
G protein-coupled receptor, which transduces the smoothened signaling pathway (PubMed:19592253, PubMed:27437577, PubMed:28344083, PubMed:31168089, PubMed:32929279, PubMed:36202993). Activated by cholesterol in response to hedgehog (DHH, IHH or SHH) morphogens (PubMed:27437577, PubMed:28344083, PubMed:32929279). In absence of hedgehog, SMO is inactivated by patched protein (PTCH1 or PTCH2), which prevents SMO access to cholesterol (PubMed:28344083). In response to hedgehog-binding to pathched, inhibition is relieved, promoting SMO translocation to primary cilium and activation by cholesterol: cholesterol causes a conformation change that triggers signaling via G protein G(i), mediating inhibition of adenylate cyclase activity and decreassed production of cAMP (PubMed:28344083, PubMed:31168089). Decreased cAMP levels then inhibit protein kinase A (PKA) and promote release of GLI (GLI1, GLI2 and GLI3) transcription factors, which activate expression of target genes (PubMed:31168089). Active SMO also directly inhibits PKA by sequestering its catalytic subunit, PRKACA, at the cell membrane, preventing PRKACA-mediated phosphorylation and subsequent processing of GLI transcription factors (PubMed:36202993, PubMed:39138140). Active SMO also promotes the removal of GPR161, a key inhibitor of the smoothened signaling pathway, from primary cilia (By similarity). {ECO:0000250|UniProtKB:P56726, ECO:0000269|PubMed:19592253, ECO:0000269|PubMed:27437577, ECO:0000269|PubMed:28344083, ECO:0000269|PubMed:31168089, ECO:0000269|PubMed:32929279, ECO:0000269|PubMed:36202993, ECO:0000269|PubMed:39138140}.
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 Withdrawn means the drug was pulled from the market or from development.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 Ligand, Druggable Family
- Antibody
- GO CC high conf, UniProt loc med conf, UniProt SigP or TMHMM
- PROTAC
- Small Molecule Binder
gnomAD loss of function constraint: o/e 0.4904100000858307 (upper bound 0.6383900046348572). 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 60 registry trials, updated in the last three years, of the most advanced drugs against SMO (sonidegib, glasdegib, vismodegib, patidegib, taladegib, BMS-833923), ranked by Phase 2+ trials. Live from ClinicalTrials.gov.
- Lisa LancasterEndeavor Biomedicines · 2 of 3 trials Phase 2+Ph1NCT07454291 · A Study to Evaluate Pharmacokinetics and Drug-drug Interactions of ENV-101 (Taladegib) in Healthy Participantsbrief
- Antoine ItalianoInstitut Bergonie Cancer Center · 2 of 2 trials Phase 2+
- Laurent MORTIERUniversity Hospital, Lille · 2 of 2 trials Phase 2+
- Albert CorneliusHelen DeVos Children's Hospital · 1 of 1 trials Phase 2+
- Ali ZarrinparUniversity of Florida · 1 of 1 trials Phase 2+
- Amar GajjarSt. Jude Children's Research Hospital · 1 of 1 trials Phase 2+
- Anne S TsaoECOG-ACRIN Cancer Research Group · 1 of 1 trials Phase 2+
- Åslaug HellandOslo University Hospital · 1 of 1 trials Phase 2+
- Chandra BelaniECOG-ACRIN Cancer Research Group · 1 of 1 trials Phase 2+
- Clement LeongAscend Biopharmaceuticals Ltd · 1 of 1 trials Phase 2+
- Daniel J RenoufBCCA - Vancouver Cancer Centre, Vancouver BC, Canada · 1 of 1 trials Phase 2+
- Deepa JeyakumarChao Family Comprehensive Cancer Center · 1 of 1 trials Phase 2+
- E.E. VoestThe Netherlands Cancer Institute · 1 of 1 trials Phase 2+
- Giles RobinsonSt. Jude Children's Research Hospital · 1 of 1 trials Phase 2+
- Giovanni MartinelliUniversity of Bologna · 1 of 1 trials Phase 2+
Registry trials of sonidegib, glasdegib, vismodegib, patidegib, taladegib, BMS-833923 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; 44 of 59 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. 1 trials list no sites and are left out. Source: ClinicalTrials.gov, fetched live.
40 trials of drugs against SMO were stopped early; 10 give no reason
Terminated, withdrawn and suspended interventional trials of sonidegib, glasdegib, vismodegib, patidegib, taladegib, BMS-833923, TAK-441, LEQ506, 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 40.
- suspended · 2026-09-18 · Dwight Owen · Vismodegib“Pending ICF update”
- terminated · 2026-07-21 · Sol-Gel Technologies, Ltd. · Patidegib Topical Gel, 2%, Patidegib Topical Gel, Vehicle“Terminated early due to low blinded event rate”
- terminated · 2025-10-23 · European Organisation for Research and Treatment of Cancer - EORTC · Sonidegib“Poor accrual”
- terminated · 2025-08-21 · Eli Lilly and Company · Taladegib“The study was terminated due to business considerations”
- terminated · 2024-10-29 · Fred Hutchinson Cancer Center · Glasdegib“Study closed to accrual early due to side effects of study drug.”
- terminated · 2024-09-24 · Sol-Gel Technologies, Ltd. · Patidegib Topical Gel, 2%“Study was terminated early due to low blinded event rate and this study termination is not related to safety of the drug Patidegib Topical Gel, 2%.”
- terminated · 2024-08-06 · Giselle Sholler · Vismodegib“Lack of enrollment and commercial availability of drug”
- terminated · 2024-03-04 · OHSU Knight Cancer Institute · Vismodegib“Low accrual”
- withdrawn · 2024-01-23 · OHSU Knight Cancer Institute · Vismodegib“Withdrawn due to a change in therapeutic interventions.”
- terminated · 2023-07-10 · M.D. Anderson Cancer Center · Taladegib“The sponsor sold the drug TALADEGIB to another company during the trial and thereafter no drug was available. The sponsor made a decision to stop development of this drug Taladegib.”
- terminated · 2022-07-01 · University Hospital Heidelberg · Glasdegib“Study turned out no longer feasible. End of Recruitment: 25.5.2022”
- withdrawn · 2022-06-09 · City of Hope Medical Center · Glasdegib Maleate“Drug availability”
- terminated · 2021-10-15 · Yale University · Glasdegib“Unable to accrue patients following COVID-19 study pause.”
- terminated · 2021-07-19 · National Cancer Institute (NCI) · VismodegibNo reason given
- terminated · 2020-01-29 · Istituto Clinico Humanitas · Vismodegib“low recruitment rate”
- terminated · 2020-01-22 · Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins · matched by the registry's drug synonyms“Study was terminated due to cease in manufacturing of study drug.”
- withdrawn · 2019-12-18 · Columbia University · Vismodegib“Loss of funding”
- terminated · 2019-08-14 · University of Arizona · Vismodegib“Low enrollment”
- withdrawn · 2019-06-19 · Martin Gutierrez · matched by the registry's drug synonymsNo reason given
- terminated · 2019-05-21 · Centre Leon Berard · vismodegib“The number of successes is not reached at the end of first stage of the phase II. The study is stopped.”
- terminated · 2019-02-28 · National Cancer Institute (NCI) · VismodegibNo reason given
- terminated · 2019-01-29 · Anne Chang · Sonidegib“Business Decision”
- terminated · 2019-01-17 · Pfizer · Glasdegib (PF-04449913)No reason given
- terminated · 2018-12-28 · Eli Lilly and Company · matched by the registry's drug synonyms“Change in clinical strategy.”
- terminated · 2018-03-19 · Massachusetts General Hospital · matched by the registry's drug synonymsNo reason given
Paediatric incentives and obligations for SMO's drugs
For sonidegib, glasdegib, vismodegib, patidegib, taladegib, BMS-833923, TAK-441, LEQ506: 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 · SMO 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 · EMA/PE/0000238063 (taladegib, Treatment of idiopathic pulmonary fibrosis): PM: decision on the application for modification of an agreed PIP, 14 Apr 2025; EMEA-000880-PIP02-11-M04 (sonidegib, Treatment of medulloblastoma): PM: decision on the application for modification of an agreed PIP, 20 Mar 2020; EMEA-002199-PIP01-17 (Glasdegib, Treatment of acute myeloid leukaemia): W: decision granting a waiver in all age groups for all conditions or indications, 15 Aug 2018; EMEA-002322-PIP01-17 (patidegib, Treatment of naevoid basal-cell carcinoma syndrome (Gorlin syndrome)): W: decision granting a waiver in all age groups for all conditions or indications, 17 Jul 2018Rule: 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/3/25/3054 positive 22 May 2025: Treatment of idiopathic pulmonary fibrosis; EU/3/18/1998 positive 21 Mar 2018: Treatment of naevoid basal-cell carcinoma syndrome (Gorlin syndrome); EU/3/17/1923 positive 16 Oct 2017: Treatment of acute myeloid leukaemiaRule: 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 · Erivedge: authorised since 12 Jul 2013; Odomzo: authorised since 14 Aug 2015; Daurismo: authorised since 26 Jun 2020, orphan medicineRule: 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 sonidegib, glasdegib, vismodegib, patidegib, taladegib, bms-833923, tak-441, leq506Rule: 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 · 10 interventional studies of sonidegib, glasdegib, vismodegib, patidegib, taladegib, bms-833923, tak-441, leq506 include patients under 18; 2 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 10 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.