A Study of LOXO-783 in Patients With Breast Cancer/Other Solid Tumors (PIKASSO-01)
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ClinicalTrials.gov Identifier: NCT05307705 |
Recruitment Status :
Recruiting
First Posted : April 1, 2022
Last Update Posted : March 29, 2023
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Breast Cancer | Drug: LOXO-783 Drug: Fulvestrant Drug: Imlunestrant Drug: Abemaciclib Drug: Anastrozole, Exemestane, or Letrozole Drug: Paclitaxel | Phase 1 |
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 400 participants |
Allocation: | Non-Randomized |
Intervention Model: | Sequential Assignment |
Masking: | None (Open Label) |
Primary Purpose: | Treatment |
Official Title: | A Study of LOXO-783 Administered as Monotherapy and in Combination With Anticancer Therapies for Patients With Advanced Breast Cancer and Other Solid Tumors With a PIK3CA H1047R Mutation |
Actual Study Start Date : | May 11, 2022 |
Estimated Primary Completion Date : | May 2025 |
Estimated Study Completion Date : | May 2025 |

Arm | Intervention/treatment |
---|---|
Experimental: Phase 1A: LOXO-783 Monotherapy Dose Escalation
LOXO-783 administered orally
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Drug: LOXO-783
Oral
Other Name: LY3849524 |
Experimental: Phase 1B: Part A
LOXO-783 administered orally in combination with fulvestrant intramuscularly, imlunestrant orally, or an aromatase inhibitor orally
|
Drug: LOXO-783
Oral
Other Name: LY3849524 Drug: Fulvestrant Intramuscular Drug: Imlunestrant Oral
Other Name: LY3484356 Drug: Anastrozole, Exemestane, or Letrozole Oral |
Experimental: Phase 1B: Part B
LOXO-783 orally in combination with abemaciclib and either physician's choice aromatase inhibitor orally, fulvestrant intramuscularly, or imlunestrant orally
|
Drug: LOXO-783
Oral
Other Name: LY3849524 Drug: Fulvestrant Intramuscular Drug: Imlunestrant Oral
Other Name: LY3484356 Drug: Abemaciclib Oral
Other Name: LY2835219 Drug: Anastrozole, Exemestane, or Letrozole Oral |
Experimental: Phase 1B: Part C
LOXO-783 orally in combination with fulvestrant intramuscularly
|
Drug: LOXO-783
Oral
Other Name: LY3849524 Drug: Fulvestrant Intramuscular |
Experimental: Phase 1B: Part D
LOXO-783 orally in combination with paclitaxel intravenously
|
Drug: LOXO-783
Oral
Other Name: LY3849524 Drug: Paclitaxel Intravenous |
Experimental: Phase 1B: Part E
LOXO-783 orally
|
Drug: LOXO-783
Oral
Other Name: LY3849524 |
Experimental: Phase 1B: Part F
Multiple randomized dose levels of LOXO-783 orally with fulvestrant intramuscularly
|
Drug: LOXO-783
Oral
Other Name: LY3849524 Drug: Fulvestrant Intramuscular |
- Phase 1 a: To determine the MTD/RP2D of LOXO-783: Number of patients with dose-limiting toxicities (DLTs) [ Time Frame: 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 [ Time Frame: During the first 28-day cycle of LOXO-783 treatment ]Number of patients with DLT-equivalent toxicities
- To assess the pharmacokinetics (PK) of LOXO-783: Area under the concentration versus time curve (AUC) [ Time Frame: Up to 2 months ]PK of LOXO-783: AUC
- To assess the PK of LOXO-783: Maximum drug concentration (Cmax) [ Time Frame: Up to 2 months ]PK of LOXO-783: Cmax
- To evaluate the preliminary antitumor activity of LOXO-783: Overall response rate (ORR) [ Time Frame: Up to approximately 36 months or 3 years ]ORR per investigator assessed RECIST 1.1
- To evaluate the preliminary antitumor activity of LOXO-783: Best overall response (BOR) [ Time Frame: Up to approximately 36 months or 3 years ]BOR per investigator assessed RECIST 1.1
- To evaluate the preliminary antitumor activity of LOXO-783: Duration of response (DOR) [ Time Frame: Up to approximately 36 months or 3 years ]DOR per investigator assessed RECIST 1.1
- To evaluate the preliminary antitumor activity of LOXO-783: Disease control rate (DCR) [ Time Frame: Up to approximately 36 months or 3 years ]DCR per investigator assessed RECIST 1.1
- To evaluate the preliminary antitumor activity of LOXO-783: Clinical benefit rate (CBR) [ Time Frame: Up to approximately 36 months or 3 years ]CBR per investigator assessed RECIST 1.1
- To evaluate the preliminary antitumor activity of LOXO-783: Time to response (TTR) [ Time Frame: Up to approximately 36 months or 3 years ]TTR per investigator assessed RECIST 1.1
- To evaluate the preliminary antitumor activity of LOXO-783: Progression free survival (PFS) [ Time Frame: Up to approximately 36 months or 3 years ]PFS per investigator assessed RECIST 1.1
- To evaluate the preliminary antitumor activity of LOXO-783: Overall survival (OS) [ Time Frame: Up to approximately 36 months or 3 years ]OS per investigator assessed RECIST 1.1

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.
Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Have advanced breast cancer or another solid tumor with the presence of a PIK3CA H1047R mutation (or other Sponsor and SRC-approved, activating PIK3CA mutations other than H1047R mutation)
- Have adequate archival tumor tissue sample available or be approved by the Sponsor for enrollment if no tumor sample is available.
- Have stopped all cancer treatment and have recovered from the major side effects
- Have adequate organ function, as measured by blood tests
- Have a performance status of 0 or 1 on the Eastern Cooperative Oncology Group (ECOG) scale
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Patients must have
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Measurable disease
--- Patients with non-breast tumor types must have at least 1 measurable lesion
- Non-measurable bone disease (at least one bone lesion in breast cancer patients only)
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For patients with an ER+ breast cancer diagnosis:
- If female, must be postmenopausal
- If male, must agree to use hormone suppression
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Phase 1a:
-- Dose escalation and backfill patients:
- Advanced solid tumor
- Patients may have had up to 5 prior regimens for advanced disease
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Phase 1b:
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Part A:
- ER+/HER2- advanced breast cancer
- Patients may have had up to 2 to 4 prior regimens for advanced disease, depending on cohort ---- Prior cyclin dependent kinase (CDK)4/6 inhibitor therapy required
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Part B:
- ER+/HER2- advanced breast cancer
- Patients may have had up to 2 prior regimens for advanced disease.
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Part C:
- ER+/HER2- advanced breast cancer
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Patients may have had up to 5 prior regimens for advanced disease.
---- Prior CDK4/6 inhibitor therapy required.
- Have a diagnosis of diabetes mellitus Type 2
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Part D:
- Advanced breast cancer
- Patients may have had up to 5 prior regimens for advanced disease.
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Part E:
- Advanced solid tumor
- Patients may have had up to 3 prior regimens for advanced disease advanced disease
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Part F:
- ER+/HER2- advanced breast cancer
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Patients may have had up to 2 prior regimens for advanced disease
- Prior cyclin dependent kinase (CDK)4/6 inhibitor therapy required
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Exclusion Criteria:
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Medical Conditions
- Colorectal cancer
- Endometrial cancers with specific concurrent oncogenic alterations
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A history of known active or suspected
- Diabetes mellitus Type 1 or
- Diabetes mellitus Type 2 requiring antidiabetic medication (Phase 1a and all parts of Phase 1b except Part C).
- Serious concomitant systemic disorder
- Known or suspected history of untreated or uncontrolled central nervous system (CNS) involvement.
- Active uncontrolled systemic bacterial, viral, fungal, or parasitic infection, or other clinically significant active disease process
- Prior exposure to PI3K/AKT/mTOR inhibitor(s), except in certain circumstances

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT05307705
Contact: Patient Advocacy | 855-569-6305 | clinicaltrials@loxooncology.com; |

Study Director: | Vincent Chau, MD; PhD | Loxo Oncology, Inc. |
Responsible Party: | Eli Lilly and Company |
ClinicalTrials.gov Identifier: | NCT05307705 |
Other Study ID Numbers: |
LOXO-PIK-21001 J4C-OX-JZUA ( Other Identifier: Eli Lilly and Company ) 2022-000175-40 ( EudraCT Number ) |
First Posted: | April 1, 2022 Key Record Dates |
Last Update Posted: | March 29, 2023 |
Last Verified: | March 2023 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
Breast Neoplasms Neoplasms by Site Neoplasms Breast Diseases Skin Diseases Paclitaxel Letrozole Fulvestrant Anastrozole Exemestane Antineoplastic Agents, Phytogenic Antineoplastic Agents Tubulin Modulators |
Antimitotic Agents Mitosis Modulators Molecular Mechanisms of Pharmacological Action Aromatase Inhibitors Steroid Synthesis Inhibitors Enzyme Inhibitors Estrogen Antagonists Hormone Antagonists Hormones, Hormone Substitutes, and Hormone Antagonists Physiological Effects of Drugs Antineoplastic Agents, Hormonal Estrogen Receptor Antagonists |