Table of contents
- Trial overview
- Who is being studied
- How the studies are designed
- What is being measured
- Key points for patients
Trial overview
The available studies of At-1501 are in people with kidney transplants and focus on prophylaxis of renal allograft rejection, which means preventing the body from rejecting the new kidney.[1][2]
Both trials are Phase 2 and are listed as Authorised.[1][2]
Who is being studied
One study includes patients undergoing kidney transplantation, while the other follows kidney transplant recipients in a long-term extension study.[2][1]
The studies are set up for people who need protection of the transplanted kidney after surgery, so the target population is narrow and specific.[1][2]
How the studies are designed
The BESTOW study is a multicenter, randomized, open-label trial, which means it is run at more than one center, participants are assigned to groups by chance, and everyone knows which treatment is being used.[2]
The BESTOW-EXTENSION study is a multicenter, open-label extension study, which means it continues follow-up after earlier treatment and collects longer-term data.[1]
The enrollment numbers listed are 192 for BESTOW and 162 for BESTOW-EXTENSION.[2][1]
What is being measured
The BESTOW study measures graft function at 12 months using estimated glomerular filtration rate (eGFR), which is a common way to estimate how well the kidney is filtering blood.[2]
The BESTOW-EXTENSION study looks mainly at safety over time, including treatment-emergent serious adverse events, treatment-emergent adverse events, and adverse events of special interest.[1]
It also tracks changes in vital signs, clinical laboratory measures, and kidney transplant medication side effects using the Modified Transplant Symptom Occurrence and Symptom Distress Scale at baseline and at 12, 24, 36, and 48 months.[1]
Key points for patients
These are transplant studies. They are not general studies for all patients; they are focused on kidney transplant surgery and follow-up.[1][2]
The main goal is prevention. The trials are trying to prevent rejection of the transplanted kidney and protect kidney function after surgery.[1][2]
Safety is a major focus. The extension study especially looks at side effects, lab results, and symptom burden over months and years.[1]
Effectiveness is also measured. The randomized study checks whether kidney graft function is better at 12 months in the At-1501 group compared with tacrolimus-based treatment.[2]
These are Phase 2 studies. That means the research is still in an early-to-mid stage and is helping to learn more about benefit and safety in a transplant setting.[1][2]



