Hello from Greycoat Research,
After a Stage 3–4 kidney disease diagnosis, one of the questions guardians most often ask is this:
How long can my cat live?
Today, instead of theory or explanations,
we would like to share real cases of cats currently being cared for at Greycoat Research,
with specific timelines based on ongoing observation.
Case 1
Stage 4 CKD Cat – Stable Case (Observed for Over 6 Months)
This cat was diagnosed on June 7, 2025, with Stage 4 chronic kidney disease.
At the time of diagnosis, the kidney marker (sCr) was 6.0 mg/dL, indicating rapid deterioration.
The goal of care was clear.
Rather than expecting improvement, the focus was on maintaining stability without further decline.
Since the protocol was introduced, the cat has been under observation for over 6 months,
and the kidney marker is currently around 4.2 mg/dL.
The sharp fluctuations seen at the time of diagnosis have not been observed since.
What is most important in this case is not short-term changes in numbers,
but the fact that a stable condition has continued for more than 6 months.
Case 2
Stage 3 CKD Cat – Long-Term Stable Case (Observed for Over 1 Year and 5 Months)
This cat began observation on October 5, 2024, with Stage 3 kidney disease (sCr 3.9 mg/dL).
Since then, observation has continued for 15 months (1 year and 5 months), and the kidney marker is currently around 2.5 mg/dL.
Throughout this period, no sharp drops or sudden deterioration have been observed up to the present.
In this case, changes in severe anemia associated with the kidney disease are also being observed on an ongoing basis.
- December 21, 2024: HCT 8.5%
- June 2025: HCT 49.9%
- As of January 17, 2026: HCT 43.0%
Without the use of external erythropoietin stimulation or blood transfusions,
stable HCT levels have been maintained for more than 13 months,
which is a key observation point in this case.
In addition, spontaneous appetite and daily vitality have continued throughout the observation period.
Case 3
Another Stage 3 CKD Cat – Stable Case (Observed for Over 4 Months)
This cat began observation on June 11, 2025, with Stage 3 kidney disease (sCr 3.6 mg/dL).
After the care routine was introduced, observation has continued for over 4 months,
and the kidney marker is currently around 3.0 mg/dL.
Compared to the initial observation point, the fluctuations have become smaller, and the condition remains stable.
What these cases show
These cases do not show dramatic or sudden reversals.
Instead, they share a common pattern: a continued trend of stability.
Even after a Stage 3–4 diagnosis, some cats are being observed to maintain daily life
without rapid deterioration for 4 months, 6 months, and over 15 months, respectively.
Not every cat follows the same path, but these real-world cases carefully suggest that
the direction of care can still matter, even in advanced stages.
What is changing now
In the past, questions about survival in Stage 3–4 CKD cats had very limited answers.
Today, however, care strategies are evolving.
Approaches that consider metabolism, inflammation, and the overall living environment together are becoming increasingly possible.
Among the cats currently being cared for at Greycoat Research, multiple cases are showing more than one year of stable survival, and these observations are still ongoing.
This suggests that, even for Stage 3–4 CKD cats, the path toward stable long-term survival,
beyond short-term responses, is becoming a realistic possibility.
We continue to collect and analyze these cases as Real World Evidence, and we use these experiences to further refine our care routines and supplement development.
We will continue to share calm, data-based observations centered on real cases.
The cases introduced in this email are based on individual real-world observations.
Results may vary by cat.
This content is not intended to diagnose, treat, or cure any disease.
Greycoat Research
