Transport of Kidney Grafts by Drone for Inter-Center Transplantation: a Safety Study. Towards a French First (RAfALREIN)
| Registry | NCT07851571, acronym RAfALREIN |
|---|---|
| Status | Not yet recruiting |
| Phase | Not applicable |
| Study type | Interventional; na, single group, masking: none, health services research |
| Enrollment | 5 (Estimated) |
| Sponsor | Nantes University Hospital (Other); collaborators: Centre Hospitalier Departemental Vendee, Delivrone SAS (drone operator), Agence de La Biomédecine |
| Conditions | Kidney Failure, Chronic, Kidney Transplantation, Delayed Graft Function, Cold Ischemia |
| Interventions | Kidney graft transport by autonomous unmanned aircraft (drone) between the procurement and transplantation centres (Other) |
| Dates | start 2027-01-15 (estimated), primary completion 2027-07-01 (estimated), completion 2028-07-01 (estimated), first posted 2026-10-01, last updated 2026-10-01 |
Related Papers Related Patents Related Grants Related Experts
All trials for Kidney Failure, Chronic All trials for Kidney Transplantation All trials of Kidney graft transport by autonomous unmanned aircraft (drone) between the procurement and transplantation centres
Cold ischemia time, the period during which a donated kidney is kept cold outside the body between its removal from the donor and its transplantation into the recipient, is one of the main modifiable factors influencing how quickly and how well a transplanted kidney starts to work and how long it lasts. In France, kidneys are usually transported between hospitals by ambulance, car, train or plane, which exposes the graft to traffic, scheduling and coordination delays. Autonomous drones could offer a fast, dedicated and predictable alternative. A human kidney was successfully transplanted after drone transport in the United States in 2019, but no transplantation after drone transport of an organ has yet been reported in Europe.
The RAfALREIN study is a pilot study designed to assess the safety and feasibility of transporting deceased-donor kidneys by autonomous drone between the Centre Hospitalier Départemental Vendée in La Roche-sur-Yon (procurement site) and Nantes University Hospital (transplantation site), within a dedicated medical air corridor subject to authorisation by the French civil aviation authority. Five adult patients will receive a kidney that has been transported by drone. Apart from the mode of transport of the graft, organ procurement, preservation, transplantation, treatments and follow-up are carried out according to usual care, with no additional examination required by the study.
The main outcome is the absence of delayed graft function, defined as no need for dialysis during the first week after transplantation. Cold ischemia time, transport time, temperature and vibrations during transport, transport costs, events preventing, delaying or interrupting drone missions, and adverse events up to 30 days after transplantation are also recorded. Participants are followed for 12 months after transplantation as part of routine care.
Study hypothesis: transport of kidney grafts by autonomous drone between two hospitals is safe, does not impair early graft function and is operationally feasible in real conditions, thereby supporting the design of a larger multicentre study.
Background. Cold ischemia time (CIT) is the main modifiable determinant of delayed graft function (DGF) and of medium- and long-term kidney graft survival; each additional hour of CIT increases the risk of graft failure and mortality. The French Ministerial Plan for Organ and Tissue Procurement and Transplantation 2022-2026 set a target mean CIT of 10 hours or less for kidney transplantation and explicitly identified drone transport of grafts as a priority lever, whereas national median CIT for deceased-donor kidney transplantation remains around 14-15 hours. Conventional transport modes (road, rail, chartered or commercial flights) are exposed to traffic, timetables, airport procedures and coordination constraints, and dedicated non-commercial flights carry a non-negligible accident risk. Unmanned aircraft systems (UAS) are already used in national medical logistics networks (blood products, vaccines, laboratory samples) and in hospital corridor programmes in the United Kingdom. In 2019, the University of Maryland Medical Center performed the first kidney transplantation after drone transport of the graft, with stable temperature, vibration levels lower than in commercial aviation and no macroscopic or histological alteration. In Europe, work on organ transport by drone remains limited to feasibility and logistic modelling studies, without reported human transplantation.
Preliminary work. Nantes University Hospital (kidney transplant unit, 160-180 kidney transplantations per year) and the organ procurement coordination of CHD Vendée have collaborated for more than ten years; Nantes receives 15 to 20 kidneys procured in La Roche-sur-Yon each year. On 2 June 2024, both centres performed an experimental drone transport of a porcine kidney on the exact route planned for this study (La Roche-sur-Yon to Nantes), with full recording of flight parameters (temperature, vibrations, flight time), absence of macroscopic graft alteration and confirmation of graft function after auto-transplantation following bilateral nephrectomy. The study also aims to determine whether drone transport reduces graft exposure to shocks and thermal variations before any extension to other transplant centres.
Design. Prospective, bicentric, open-label, non-randomised, single-arm pilot study including 5 kidney transplant recipients. The procurement centre is CHD Vendée (La Roche-sur-Yon); the transplantation centre is Nantes University Hospital. The study is a first step towards a larger study (letter of intent submitted to the French PREPS programme, DGOS, December 2025).
Transport chain. After standard procurement, the kidney is packaged in a refrigerated container clinically approved for graft transport, using either static cold storage or hypothermic machine perfusion (both modes may be used in the study). The container is flown by an autonomous vertical take-off and landing fixed-wing drone (RigiTech Eiger: maximum take-off mass 21 kg, maximum payload 3 kg / 15 L, cruise speed about 104 km/h, operational wind limits 12 m/s in multirotor phase and 15 m/s in fixed-wing phase; ballistic parachute with independent failsafe unit, redundant navigation sensors, dual command-and-control links). Flights are operated beyond visual line of sight by the specialised operator Delivrone within the European 'specific' category framework, on the basis of a SORA risk assessment (SAIL II) and an operational authorisation from the French civil aviation safety directorate (DSAC), within a dedicated medical air corridor between La Roche-sur-Yon and Nantes (about 62 km as the crow flies; 75 to 88 km along the planned flight path).
Data recorded. Donor characteristics (age, sex, donor type, anthropometry, cause of death, cardiovascular history, cardiac arrest, last-hour diuresis, creatinine, proteinuria, haematuria, vasopressors); complete transport timeline (ground transfer before flight, loading, flight, ground transfer after landing); temperature and three-axis vibrations measured by a sterile sensor in contact with the graft; perfusion machine alarms if applicable; weather and corridor data and any technical incident; pre-implantation biopsy (acute glomerular, interstitial, tubular, vascular and peritubular capillary lesions, infarction or haemorrhage); recipient and surgical data (cold and warm ischemia, number of arteries, ureteral stent, time on waiting list and on dialysis); early graft function during the first post-operative week (dialysis sessions, primary non-function, serum creatinine, estimated glomerular filtration rate); follow-up visits at D10-D30, M1-M3 and M3-M12 (biology, urinalysis, ultrasound as clinically indicated, uro-vascular complications, maintenance immunosuppression, return to dialysis, graft nephrectomy, death). All clinical data derive from routine care.
Missions not completed by drone. If the drone cannot take off (adverse weather, winds above operational limits, regulatory unavailability or saturation of the corridor, technical issue) or if the mission is interrupted in flight (automatic return to base or landing in a predefined safe area), the graft is immediately transferred by conventional transport according to standard pathways, with no loss of chance for the recipient. In that case the recipient is not included in the drone-transport analysis, but every planned mission, including delayed, cancelled or aborted missions, is systematically documented and analysed to identify limiting factors.
Statistical analysis. Analyses are descriptive. The primary outcome is expressed as the proportion of recipients without DGF with its exact 95% confidence interval (Clopper-Pearson). Quantitative secondary outcomes are described (mean, standard deviation, median, minimum, maximum) with individual presentation by patient and by mission. No comparative or confirmatory analysis, no significance threshold, no interim analysis and no imputation of missing data are planned. The analysis population comprises all recipients transplanted with a graft effectively transported by drone (as treated); the transport safety analysis includes all planned drone missions.
Budget impact. Transport costs of the study grafts, based on invoices, will be compared with mean transport costs observed in 2024 and 2025 (between Nantes and CHD Vendée, and between these centres and other national centres), from the hospital perspective, with a projection of the annual financial impact of deploying drone transport at Nantes University Hospital.
| Arm | Type | Interventions | Description |
|---|---|---|---|
| Drone-transported kidney graft | Experimental | Other: Kidney graft transport by autonomous unmanned aircraft (drone) between the procurement and transplantation centres | Adult recipients transplanted at Nantes University Hospital with a deceased-donor kidney procured at CHD Vendée (La Roche-sur-Yon) and transported to Nantes by autonomous drone. Procurement, preservation (static cold storage or hypothermic machine perfusion), transplantation, immunosuppression and 12-month follow-up are performed according to standard care. If the drone cannot take off or the mission is interrupted, the graft is transferred by conventional transport and the recipient is not included; the mission is recorded for the transport safety analysis. |
Sex: All, ages: 18 Years to any
Inclusion Criteria: * Male or female aged 18 years or older, scheduled to receive a kidney transplant at Nantes University Hospital from a deceased donor (brain death or controlled donation after circulatory death) * Kidney graft procured at CHD Vendée (La Roche-sur-Yon) and effectively transported by drone (study population, protocol section 5.1) * Affiliation to a social security scheme * Oral consent to participate, recorded in the medical file (inclusion on the day of transplantation, day 0) Donor criteria: donor aged 18 years or older, brain-dead donor or controlled donation after circulatory death Exclusion Criteria: * Adult under guardianship or curatorship * Pregnant or breastfeeding woman