Recent Updates
Recently added Catalysts

LOXO-783

Phase 1

Breast Cancer | Small molecule | Oncology |Eli Lilly and Company|Last Updated: Aug 7, 2026

Target and mechanism

Molecular targetPI3Kα H1047R
Target classProtein
ModalitySmall molecule

Success Probability

Subscribe to view

Market & Valuation

Subscribe to view

Trial Design

CONTROLLED
Total Trials1
Total Enrollment260

FDA Designations

No designations recorded

Clinical trial landscape

LOXO-783 · 4 trials · 2 indications

Phase 1 4
NCT06102512A Study of [14C]-LOXO-783 in Healthy Adult ParticipantsHealthy
COMPLETED16 Analytics
NCT06028425A Study to Evaluate the Effect of Food on LOXO-783 in Healthy ParticipantsHealthy
COMPLETED42 Analytics
NCT05894928A Study to Evaluate the Effect of Cholestyramine on LOXO-783 in Healthy ParticipantsHealthy
COMPLETED21 Analytics
NCT05307705A Study of LOXO-783 in Patients With Breast Cancer/Other Solid TumorsBreast Cancer
RECRUITING260 Analytics
PHASE1COMPLETED
A Study of [14C]-LOXO-783 in Healthy Adult Participants
HealthyUnlock trial analytics
PHASE1COMPLETED
A Study to Evaluate the Effect of Food on LOXO-783 in Healthy Participants
HealthyUnlock trial analytics
PHASE1COMPLETED
A Study to Evaluate the Effect of Cholestyramine on LOXO-783 in Healthy Participants
HealthyUnlock trial analytics
PHASE1RECRUITING
A Study of LOXO-783 in Patients With Breast Cancer/Other Solid Tumors
Breast CancerUnlock trial analytics

Study Endpoints

Primary Endpoints

Pharmacokinetics (PK): Fraction of Dose Excreted in Urine (Feur)
Predose on day 1 up to postdose on day 21 (Part 1)

PK: Feur

PK: Cumulative Feur
Predose on day 1 up to postdose on day 21 (Part 1)
PK: Fraction of Dose Excreted in Feces (Fefeces)
Predose on day 1 up to postdose on day 21 (Part 1)

PK: Fefeces

PK: Cumulative Fefeces
Predose on day 1 up to postdose on day 21 (Part 1)
PK: Fraction of Dose Excreted in Expired Air (Feair)
Predose on day 1 up to postdose on day 21 (Part 1)

PK: Feair

PK: Absolute Bioavailability (F) of LOXO-783
Predose on day 1 up to postdose on day 9 (Part 2)

PK: F of LOXO-783

Pharmacokinetics (PK): Maximum Observed Concentration (Cmax) of LOXO-783
Predose on Day 1 up to 96 hours postdose

PK: Cmax of LOXO-783

PK: Area Under the Concentration-Time Curve (AUC) from Time 0 to Infinity (AUC [0-∞]) of LOXO-783
Predose on Day 1 up to 96 hours postdose

PK: AUC \[0-∞\] of LOXO-783

PK: Area Under the Concentration-Time Curve (AUC) from Time 0 to Infinity (AUC[0-inf]) of LOXO-783
Predose on Day 1 upto 96 hours postdose of each treatment period

PK: AUC(0-inf) of LOXO-783

Phase 1 a: To determine the maximum tolerated dose/recommended phase 2 dose (MTD/RP2D) of LOXO-783: Number of patients with dose-limiting toxicities (DLTs)
During the first 28-day cycle of LOXO-783 treatment

Number of patients with DLTs

Phase 1 a: To determine the MTD/RP2D of LOXO-783: Number of patients with DLT-equivalent toxicities
During the first 28-day cycle of LOXO-783 treatment

Number of patients with DLT-equivalent toxicities

Secondary Endpoints

To assess the pharmacokinetics (PK) of LOXO-783: Area under the concentration versus time curve (AUC)
Up to 2 months
To assess the PK of LOXO-783: Maximum drug concentration (Cmax)
Up to 2 months
To evaluate the preliminary antitumor activity of LOXO-783: Overall response rate (ORR)
Up to approximately 36 months or 3 years
Unlock Study Endpoints

Study Design & Arms

AllocationNON_RANDOMIZED
MaskingNONE
ModelPARALLEL
PurposeBASIC_SCIENCE

Treatment Arms

ArmTypeDescription
[¹⁴C]-LOXO-783 (Part 1)EXPERIMENTALSingle dose of \[¹⁴C\]-LOXO-783 administered orally
LOXO-783 + [¹⁴C]-LOXO-783 (Part 2)EXPERIMENTALSingle dose of LOXO-783 administered orally followed by single dose of \[¹⁴C\]-LOXO-783 administered intravenously (IV)
LOXO-783 (Fasted State)EXPERIMENTALLOXO-783 administered orally to participants who are in fasted state
LOXO-783 (Fed State - Low Fat Meal)EXPERIMENTALLOXO-783 administered orally to participants who are on low fat meal
LOXO-783 (Fed State - High Fat Meal)EXPERIMENTALLOXO-783 administered orally to participants who are on high fat meal
LOXO-783 aloneEXPERIMENTALSingle dose of LOXO-783 administered orally.
LOXO-783 + Cholestyramine 1 hour post doseEXPERIMENTALSingle dose of LOXO-783 administered orally followed by a single dose of cholestyramine administered orally after 1 hour.
LOXO-783 + Cholestyramine 4 hours post doseEXPERIMENTALSingle dose of LOXO-783 administered orally followed by a single dose of cholestyramine administered orally after 4 hours.
Phase 1A: LOXO-783 Monotherapy Dose EscalationEXPERIMENTALLOXO-783 administered orally
Phase 1B: Part AEXPERIMENTALLOXO-783 administered orally in combination with fulvestrant intramuscularly, imlunestrant orally, or an aromatase inhibitor orally
Phase 1B: Part BEXPERIMENTALLOXO-783 orally in combination with abemaciclib and either physician's choice aromatase inhibitor orally, fulvestrant intramuscularly, or imlunestrant orally
Phase 1B: Part CEXPERIMENTALLOXO-783 orally in combination with fulvestrant intramuscularly
Phase 1B: Part DEXPERIMENTALLOXO-783 orally in combination with paclitaxel intravenously
Phase 1B: Part EEXPERIMENTALLOXO-783 orally
Phase 1B: Part FEXPERIMENTALMultiple randomized dose levels of LOXO-783 orally with fulvestrant intramuscularly

Interventions

NameTypeDescription
[¹⁴C]-LOXO-783DRUGAdministered orally
LOXO-783DRUGAdministered orally
CholestyramineDRUGAdministered orally.
FulvestrantDRUGIntramuscular
ImlunestrantDRUGOral
AbemaciclibDRUGOral
Anastrozole, Exemestane, or LetrozoleDRUGOral
PaclitaxelDRUGIntravenous
Unlock Study Design Details

Eligibility Criteria

Age Range18 Years to 55 Years
SexALL
Healthy VolunteersYes
Study Sites1

Inclusion Criteria: * Male and female participants in good health, determined by no clinically significant findings from medical history, physical examination, ECGs, vital signs, and clinical laboratory evaluations as assessed by the investigator * Have a body mass index within the range 18.5 to 32...

Countries:United StatesAustraliaBelgiumCanadaChinaFranceGermanyJapanSingaporeSouth KoreaSpainUnited Kingdom
Unlock Eligibility Criteria

Competitive Landscape -Breast Cancer 402 trials

Top 20 of 92 competitors

CompanyTickerTrialsLead PhaseDrugs
AstraZeneca PLCAZN47PHASE3Fulvestrant, Capivasertib
Merck & Co., Inc.MRK12PHASE3Pembrolizumab, Paclitaxel, Doxorubicin, Epirubicin, Cyclophosphamide
Eli Lilly and CompanyLLY27PHASE3Abemaciclib, Standard Adjuvant Endocrine Therapy
BioNTech SE Sponsored ADRBNTX7PHASE3DB-1303/BNT323, T-DM1
Gilead Sciences, Inc.GILD13PHASE3Sacituzumab Govitecan-hziy, Eribulin, Capecitabine Product, Gemcitabine, Vinorelbine
Novartis AG Sponsored ADRNVS30PHASE3Ribociclib
Pfizer Inc.PFE34PHASE3ARV-471, Fulvestrant
BeOne Medicines Ltd. Sponsored ADRONC5PHASE3BGB-43395, Letrozole, Abemaciclib, Palbociclib, Ribociclib
Olema Pharmaceuticals, Inc.OLMA5PHASE3Palazestrant, Fulvestrant, Anastrozole, Letrozole, Exemestane
Jazz Pharmaceuticals Public Limited CompanyJAZZ3PHASE3Zanidatamab, Trastuzumab, Eribulin, Vinorelbine, Gemcitabine
Celcuity Inc.CELC3PHASE3Gedatolisib, Palbociclib, Fulvestrant, Alpelisib
Relay Therapeutics, Inc.RLAY2PHASE3Zovegalisib, Capivasertib, Fulvestrant
GSK plc Sponsored ADRGSK2PHASE3Niraparib
Greenwich LifeSciences, Inc.GLSI1PHASE3GLSI-100
Bristol-Myers Squibb CompanyBMY5PHASE2Iza-bren, Nab-paclitaxel, Paclitaxel, Capecitabine, Carboplatin
BriaCell Therapeutics CorpBCTX2PHASE3SV-BR-1-GM, Cyclophosphamide, Interferon infiltration of the inoculation site, Retifanlimab, Treatment of Physician's Choice
Incyte CorporationINCY4PHASE2Ruxolitinib, Capecitabine, Regorafenib
Natera, Inc.NTRA3PHASE2Discontinuation of the anti-HER2 maintenance therapy
Puma Biotechnology, Inc.PBYI3PHASE2Neratinib, Loperamide, Colesevelam
Atossa Therapeutics, Inc.ATOS1PHASE2endoxifen, goserelin
Unlock Competitive Intelligence

Recent Changes (Last 90 Days)

LOWAug 7, 2026NCT05307705lastUpdatePostDate: changed
LOWAug 7, 2026NCT05307705lastUpdatePostDate: changed
LOWJul 20, 2026NCT05307705Status: ACTIVE_NOT_RECRUITING → RECRUITING
LOWJul 20, 2026NCT05307705Status: ACTIVE_NOT_RECRUITING → RECRUITING

Frequently asked questions about LOXO-783

What is LOXO-783 used for in breast cancer?

LOXO-783 is an investigational small molecule being studied for the treatment of breast cancer and other solid tumors. It is currently in Phase 1 clinical development, with an active trial enrolling patients with breast cancer. The drug is not yet approved and remains under investigation for safety and efficacy.

What does LOXO-783 target?

LOXO-783 targets the PI3Kα H1047R mutation, a specific alteration in the PI3Kα protein. This molecular target is relevant in oncology, as the mutation can drive tumor growth. By targeting this specific form of PI3Kα, LOXO-783 aims to interfere with cancer cell signaling pathways.

Who is developing LOXO-783?

LOXO-783 is being developed by Eli Lilly and Company, a pharmaceutical company listed on the New York Stock Exchange under the ticker symbol LLY. The company is conducting clinical trials to evaluate the drug's safety and effectiveness in patients with breast cancer and other solid tumors.

What phase is LOXO-783 in?

LOXO-783 is in Phase 1 clinical development. It is an investigational drug, meaning it has not been approved by regulatory authorities. The active Phase 1 trial is recruiting participants with breast cancer to assess the drug's safety, tolerability, and pharmacokinetics.

What clinical trials is LOXO-783 in?

LOXO-783 is being studied in several clinical trials. The main active trial is NCT05307705, a Phase 1 study in patients with breast cancer or other solid tumors, enrolling 260 participants across multiple countries. Completed trials include NCT05894928, NCT06028425, and NCT06102512, which evaluated the drug in healthy participants.

Is LOXO-783 the same as any other drug?

LOXO-783 is the primary name for this investigational drug. No alternative names have been reported in the clinical trial information. It is a distinct small molecule being developed by Eli Lilly and Company for potential use in oncology.