# K261856: Halcyon, Ethos Radiotherapy System (5.0)

- Pathway: 510(k) (Traditional)
- Applicant: Varian Medical Systems, Inc.
- Decided: Aug 3, 2026 after 60 days
- Product code: IYE (Accelerator, Linear, Medical)
- Device class: 2
- Regulation: 21 CFR 892.5050
- Recalls of this device: none
- Data: FDA decisions to Oct 25, 2026; recalls to Oct 12, 2026

## Lineage
Longest line of descent: 19 generations back to K010975 (2001). 65 ancestors in all.
No later device cites it as a predicate yet.
0 of 66 devices in its family (counting itself) have a Class I recall.

## Predicates on the family tree (from the FDA summary)
- K252977: Halcyon, Ethos Radiotherapy System (5.0), Varian Medical Systems, Inc. (2026) Summary page 5.

## Indications for use
Halcyon and Ethos radiotherapy system are indicated for the delivery of stereotactic radiosurgery and precision radiotherapy for lesions, tumors, and conditions anywhere in the body where radiation is indicated for adults and pediatric patients. Halcyon and Ethos radiotherapy system with the HyperSight imaging feature produce kV CBCT anatomical images that can be used in the simulation and planning of radiation therapy. The Halcyon and Ethos Radiotherapy systems may be used in the delivery of radiation treatment for adults with the following non-cancerous medically refractory hyperproliferative disorders: Dupuytren's contracture, Ledderhose disease, heterotopic ossification, and keloids; and low dose radiotherapy for adults with non-cancerous medically refractory osteoarthritis; and the following periarticular soft tissue disorders: plantar fasciitis, shoulder syndrome, trochanteric bursitis, and tennis/golf elbow.

Source page: https://510kreport.com/device/K261856
Methodology: https://510kreport.com/methodology