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Inluriyo ™ (imlunestrant) tablets
200 mg
This information is provided in response to your request. Resources may contain information about doses, uses, formulations and populations different from product labeling. See Prescribing Information above, if applicable.
Can Inluriyo™ (imlunestrant) be taken with or without food?
A low-fat meal increased the exposure of imlunestrant with regards to AUC and Cmax, therefore patients should take imlunestrant on an empty stomach at least 2 hours before or 1 hour after food.
Phase 1 Study of the Effect of Food and Gastric pH Change on the Pharmacokinetics and Safety of Imlunestrant in Healthy Females
Overview
An open-label phase 1 study (NCT04840888) was conducted to evaluate the effect of food intake (cohort 1) and gastric pH change due to omeprazole (cohort 2) on the pharmacokinetics (PK) and safety and tolerability of imlunestrant in healthy adult females. In this document, only cohort 1 data are presented.1,2
Methods
Patients in cohort 1 were randomized 1:1 to a crossover sequence to receive imlunestrant either in a fasted followed by a fed state, or a fed followed by a fasted state. All patients received a single dose of 400 mg in the fed or fasted state with a washout period of 4 days between doses. A low-fat meal (500 calories with 13% fat) was used to assess the food effect in the fed state.2
The PK parameters assessed were
- area under the concentration (AUC) versus time curve from time zero to time tlast, where tlast is the last sampling time point, which was 96 hours post-dose [AUC(0-tlast) = (0-96h)]
- AUC versus time curve from time zero to infinity [AUC(0-∞)]
- maximum observed drug concentration (Cmax)
- time of maximum observed drug concentration (Tmax)
- half-life (t½), and
- apparent total body clearance of drug after extravascular administration (CL/F).2
Results
A total of 8 patients were enrolled in cohort 1. Imlunestrant Pharmacokinetic Measurements of Cohort 1 of the Study presents the assessed PK parameters. Compared to fasted state, the fed state showed a statistically significant increase in the geometric least squares mean ratios of
- 1.99 for AUC(0-96h) (90% CI: 1.67-2.36)
- 2.04 for AUC(0-∞) (90% CI: 1.41-2.94), and
- 3.55 for Cmax (90% CI: 2.83-4.45).2
Geometric Meana | Fasted State | Fed State |
AUC(0-96h), ng.h/mL | 1830 (43) | 3900 (36) |
AUC(0-∞), ng.h/mLb | 1810 (59) | 4350 (39) |
Cmax, ng/mL | 37.2 (51) | 143 (28) |
Tmax, hours, median (range) | 8.00 (3.00-35.80) | 3.02 (2.00-8.00) |
t½, hours, geometric mean (range)b | 29.4 (26.7-35.8) | 31.3 (25.7-41.6) |
CL/F, L/hb | 221 (59) | 92.0 (39) |
Abbreviations: AUC(0-∞) = area under the concentration versus time curve from time zero to infinity; AUC(0‑96h) = area under the concentration versus time curve from time zero to time t, where t is the last time point with a measurable concentration, which was 96 hours post-dose; CL/F = apparent total body clearance of drug calculated after extravascular administration; Cmax = maximum observed drug concentration; CV = coefficient of variation; Tmax = time of maximum observed drug concentration; t½ = half-life.
aData presented as Geometric CV [%] unless otherwise specified.
bn=4
Imlunestrant was generally well tolerated when given in the fasted or fed state and there were no clinically meaningful findings in clinical laboratory assessments, vital signs, 12-lead electrocardiogram, and physical examinations. There was one patient who experienced abdominal pain in the fasted state and one patient who experienced constipation in the fed state; both were mild.2
Conclusions
A single 400 mg oral dose of imlunestrant was generally well tolerated in healthy females regardless of food intake. A low-fat diet impacted imlunestrant exposure with AUC increasing approximately 2-fold and Cmax increasing approximately 3.6-fold. Fed state Cmax at 400 mg exceeded those observed with fasted doses up to 1200 mg once daily during phase 1 development. The fasting window was adopted as a precautionary measure given the potential for increased exposures with repeated daily dosing in the presence of food.2 As such, the tablets should be taken on an empty stomach at least 2 hours before or 1 hour after food.3
Recommended Imlunestrant Administration Relative to Food Intake depicts when food may be consumed relative to imlunestrant administration.
Figure 1 description: Patients should take imlunestrant on an empty stomach at least 2 hours before or 1 hour after food.
Additional Information
The imlunestrant US prescribing information (USPI) states the following regarding administration on an empty stomach:
In Section 2.2 Recommended Dosage and Administration:
Take on an empty stomach at least 2 hours before food, or 1 hour after food [see Clinical Pharmacology (12.3)]. Take imlunestrant tablets at approximately the same time daily. Swallow the tablets whole. Do not split, crush, or chew the tablets.3
This recommendation is supported by the following section in the USPI:
In Section 12.3 Pharmacokinetics:
Effect of Food
Imlunestrant AUC increased 2-fold and Cmax increased 3.6-fold following administration with a low-fat meal (approximately 475 calories with 13% fat, 16% protein, and 71% carbohydrates). The effect of a high-fat meal (approximately 800-1,000 calories with 500-600 calories from fat) on imlunestrant exposures is unknown.3
Eli Lilly and Company can confirm that
- the text above in the imlunestrant USPI is aligned with the food effect pharmacokinetics study in a healthy volunteer
- the wording used in the USPI was recommended by the Food and Drug Administration (FDA) based on the results from the food-effect study that were previously presented at the American Association of Pharmaceutical Scientists (AAPS) meeting in 20244, and
- no further information beyond this is currently available on this topic.
The USPI for imlunestrant includes the language: “take on an empty stomach at least 2 hours before or 1 hour after food”, which reflects FDA’s recent efforts to standardize food-related dosing instructions, particularly for drugs approved after the 2022 FDA guidance was issued.3,5 While this food-effect study was initiated prior to the release of the 2022 guidance, the USPI reflects both the food-effect study findings and the FDA’s updated expectations for labeling clarity.4,5
While ingesting imlunestrant with a low-fat meal has been shown to increase absorption, variability may exist depending on the patient and the food consumed.6
Enclosed Prescribing Information
References
The published reference below is available by contacting 1-800-LillyRx (1-800-545-5979).
1A study of LY3484356 in healthy female participants. ClinicalTrials.gov identifier: NCT04840888. Updated December 11, 2025. Accessed March 2, 2026. https://www.clinicaltrials.gov/study/NCT04840888
2Datta-Mannan A, Shanks E, Yuen E, et al. Phase 1 study evaluating the effect of food and omeprazole-induced gastric pH change on the pharmacokinetics and safety of imlunestrant in healthy females. Clin Ther. 2026;48(1):81-87. https://doi.org/10.1016/j.clinthera.2025.10.007
3Inluriyo [package insert]. Indianapolis, IN: Eli Lilly and Company; 2025.
4Datta-Mannan A, Shanks E, Yuen E, et al. Evaluation of the effect of food and gastric pH change on the pharmacokinetics and safety of imlunestrant in healthy volunteers. Poster presented at: Annual Meeting of the American Association of Pharmaceutical Scientists (AAPS) - PharmSci 360; October 20-23, 2024; Salt Lake City, UT. Accessed November 4, 2024. https://aaps2024.eventscribe.net/ajaxcalls/PosterInfo.asp?PosterID=679141
5US Department of Health and Human Services, Food and Drug Administration, Center for Drug Evaluation and Research (CDER). Assessing the effects of food on drugs in INDs and NDAs – clinical pharmacology considerations: guidance for industry. June 2022. Accessed October 21, 2025. https://www.fda.gov/regulatory-information/search-fda-guidance-documents/assessing-effects-food-drugs-inds-and-ndas-clinical-pharmacology-considerations
6Data on file, Eli Lilly and Company and/or one of its subsidiaries.
Date of Last Review: April 12, 2026