EndoTwin-W

Clinical Decision Support System v3.6
CONFIDENTIAL - Authorized Personnel Only
Epigenuity LLC / R. Goyal

EndoTwin-W Clinical Decision Support

v3.6

Patient Assessment

Mid-secretory phase (days 19-23) optimal for PRS assessment

Serial Biomarker Sampling

Progesterone Resistance Score (PRS)

PRS Grade --
Decidualization
Inflammation

Circulating Biomarker Assessment

Condition Pathway Disruption Fingerprint

Predicted Gene Expression Changes (16 Target Genes)

GeneCategoryPredicted log2FCDirectionGap Detected

Clinical Summary Report

FDA Regulatory Determination

EndoTwin-W v3.6 is exempt from FDA device regulation.
This software qualifies as non-device Clinical Decision Support (CDS) under the 21st Century Cures Act, Section 3060(a), which amended the Federal Food, Drug, and Cosmetic Act to add Section 520(o)(1)(E).

Legal Basis

Section 3060(a) of the 21st Century Cures Act (Pub. L. 114-255, enacted December 13, 2016) amended Section 520 of the Federal Food, Drug, and Cosmetic Act (21 U.S.C. 360j) to add subsection (o), which excludes certain clinical decision support software from the definition of a "device" under Section 201(h) of the FD&C Act. Software meeting all four criteria of Section 520(o)(1)(E) is not a medical device and requires no FDA clearance, approval, or registration.

FDA guidance: "Changes to Existing Medical Software Policies Resulting from Section 3060 of the 21st Century Cures Act" (January 2026, superseding September 2022 version). Available at: FDA.gov Guidance Documents.

Four-Criteria Determination Under Section 520(o)(1)(E)

# Statutory Criterion EndoTwin-W Determination Met?
1 Not intended to acquire, process, or analyze a medical image, a signal from an in vitro diagnostic device, or a pattern or signal from a signal acquisition system. EndoTwin-W accepts numerical laboratory values (glycodelin-A and CA-125 concentrations) manually entered from a standard blood draw report. It does not process medical images, raw IVD instrument signals, or signal acquisition patterns. Yes
2 Intended for the purpose of displaying, analyzing, or printing medical information about a patient or other medical information. EndoTwin-W analyzes and displays patient-specific medical information: Progesterone Resistance Score, pathway disruption profiles, predicted gene expression changes, biomarker assessment, and window-of-implantation timing predictions. Yes
3 Intended for the purpose of supporting or providing recommendations to a health care professional about prevention, diagnosis, or treatment of a disease or condition. EndoTwin-W provides recommendations to OB/GYN physicians regarding endometrial receptivity assessment, progesterone resistance classification, and condition-specific pathway disruptions to guide fertility treatment decisions. Yes
4 Intended for the purpose of enabling such health care professional to independently review the basis for such recommendations so that it is not the intent that the professional rely primarily on any of such recommendations to make a clinical decision regarding an individual patient. EndoTwin-W displays full mechanistic transparency: individual pathway disruption scores, per-gene predicted expression changes with fold-change magnitudes, underlying biomarker values, radar visualization of pathway contributions, and gap detection analysis. The clinician can independently evaluate the basis for every recommendation and is expected to exercise independent clinical judgment. Yes
Determination: EndoTwin-W v3.6 meets all four criteria of Section 520(o)(1)(E) of the FD&C Act. It is therefore not a device as defined under Section 201(h) and is exempt from FDA premarket review, clearance, approval, and establishment registration requirements. This determination is made by Epigenuity LLC and documented in the regulatory file dated May 1, 2026.

References: 21st Century Cures Act, Pub. L. 114-255, Section 3060(a) (2016); 21 U.S.C. 360j(o)(1)(E); FDA Guidance, "Changes to Existing Medical Software Policies Resulting from Section 3060 of the 21st Century Cures Act" (January 2026).

Clinical Decision Support Tool. EndoTwin-W v3.6 is a CDS tool exempt from FDA device regulation under 21st Century Cures Act, Section 3060(a), meeting all four criteria of Section 520(o)(1)(E) of the FD&C Act. It is intended to support, not replace, the independent clinical judgment of a qualified healthcare professional. Model validated against 531 samples from 13 independent transcriptomic datasets (100% direction concordance, 78/78 gene-condition pairs). Epigenuity LLC.