Cleared Traditional

K252977 - Halcyon, Ethos Radiotherapy System (5.0) (FDA 510(k) Clearance)

Class II Radiology device cleared through predicate-based substantial equivalence - typically does not require clinical trials.

K252977 · Varian Medical Systems, Inc. · Radiology device
Download Printable Device Report (PDF)
Optimized for regulatory review, auditing and printing
Jan 2026
Decision
126d
Days
Class 2
Risk

K252977 is an FDA 510(k) clearance for the Halcyon, Ethos Radiotherapy System (5.0). Classified as Accelerator, Linear, Medical (product code IYE), Class II - Special Controls.

Submitted by Varian Medical Systems, Inc. (Palo Alto, US). The FDA issued a Cleared decision on January 21, 2026 after a review of 126 days - within the typical 510(k) review window.

This device falls under the Radiology FDA review panel, regulated under 21 CFR 892.5050 - the FDA radiology and imaging software oversight framework. The Traditional 510(k) pathway establishes clearance through substantial equivalence to a legally marketed predicate device, without requiring clinical trial data.

Device pattern: Standard predicate-based submission. Standard predicate reliance. This clearance follows a standard predicate-based equivalence path within the Radiology review framework, consistent with the majority of Class II 510(k) submissions.

View all Varian Medical Systems, Inc. devices

Submission Details

510(k) Number K252977 FDA.gov
FDA Decision Cleared Substantially Equivalent - Traditional 510(k) (SESE)
Date Received September 17, 2025
Decision Date January 21, 2026
Days to Decision 126 days
Submission Type Traditional
Review Panel Radiology (RA)
Summary Summary PDF
Third-party Review No - reviewed directly by FDA
Combination Product No
PCCP Authorized No
Regulatory Context
Review time vs. panel average
19d slower than avg
Panel avg: 107d · This submission: 126d
Pathway characteristics
Predicate-based equivalence. No clinical trials required.

Device Classification

Product Code IYE Accelerator, Linear, Medical
Device Class Class 2 - Special Controls
CFR Regulation 21 CFR 892.5050
What this classification means

Class II devices require demonstration of substantial equivalence to a legally marketed predicate device. This pathway does not require clinical trials - it relies on engineering equivalence and performance data. Most Radiology devices follow this clearance model.

Regulatory Peers - IYE Accelerator, Linear, Medical

All 730
Devices cleared under the same product code (IYE) and FDA review panel - the closest regulatory comparables to K252977.
VERIQA RT EPID 3D
K252258 · Ptw-Freiburg Physikalisch-Technische-Werkstaetten Dr. Pychla · Apr 2026
ClearCheck (RADCC V2.7)
K253962 · Radformation, Inc. · Apr 2026
AlignRT Plus (8.0)
K253012 · Vision Rt, Ltd. · Mar 2026
EMLA (Elekta Evo)
K252188 · Elekta Solutions AB · Jan 2026
ExacTrac Dynamic (2.0.2)
K254010 · Brainlab SE · Jan 2026
ChartCheck (RADCH V1.6)
K252988 · Radformation, Inc. · Jan 2026