Buried within ProKidney's recent Q3 2023 earnings call lies a tantalizing clue, one that may have slipped past even the most seasoned Wall Street analysts. While the company announced delays in their Phase III trials and a manufacturing pause, the underlying data from their Phase II RMCL-002 study whispers of a potential revolution in chronic kidney disease treatment. The secret weapon? Preservation of kidney function, a feat largely unheard of in the world of advanced CKD, particularly in the high-risk Stage 4 patient population.

The buzzword in the nephrology field has long been 'slowing the decline' of kidney function. Medications like SGLT2 inhibitors, while offering some benefit, still result in a gradual loss of kidney function over time. ProKidney's REACT cell therapy, however, appears to go a step further, halting that decline altogether in a significant percentage of patients.

This wasn't just a marginal improvement. The data, while preliminary, showed a staggering 37% of patients injected with REACT experiencing no decline or minimal decline in kidney function over 30 months. To put this in perspective, current standard-of-care treatments typically result in a loss of around 4-5 points of estimated glomerular filtration rate (eGFR) per year. REACT, in these patients, brought that number down to essentially zero.

Even more striking, this preservation of function was most pronounced in the sickest patients, those with Stage 4 CKD and severe albuminuria (high levels of protein in the urine). These individuals, facing the grim prospect of dialysis, found their kidney function essentially frozen in time after receiving REACT. For them, the therapy wasn't just slowing the inevitable; it seemed to be rewriting their future.

While the overall average change in eGFR for the active treatment group was a modest -3.2 ml over 30 months, this figure masks the dramatic impact observed in that key 37% subgroup. It's like averaging the grades of a class where a third of the students scored perfect scores – the average might be decent, but it doesn't capture the brilliance of those top performers.

This 'hidden gem' within the data underscores the potential for REACT to be a game-changer, not just for ProKidney, but for millions of patients worldwide facing the specter of dialysis. While the company focuses on refining their Phase III trials and addressing manufacturing concerns, this nugget of preserved kidney function should spark excitement and hope in a field desperately seeking new solutions.

The Hypothesis:

Could this preservation of function be a lasting effect? Could REACT be offering a chance at a truly dialysis-free life for some patients? It's a bold hypothesis, but one supported by these early data points. If ProKidney can demonstrate this sustained benefit in their larger, controlled Phase III trials, the impact would be seismic.

The Numbers:

37% of patients injected with REACT experienced no decline or minimal decline in eGFR over 30 months. Stage 4 CKD patients with severe albuminuria saw a 6 ml decline in eGFR in the 12 months before receiving REACT. After receiving REACT, their eGFR remained stable, with essentially zero decline over the next 18 months.

Visualizing eGFR Change

The following table summarizes the eGFR changes observed in the ProKidney Phase II RMCL-002 study:

These numbers, while preliminary, paint a picture of a therapy with the potential to rewrite the rules of CKD treatment. It's a story of hope, innovation, and a company daring to chase a seemingly impossible dream – a dialysis-free future for patients facing a life-altering diagnosis.

"Fun Fact: ProKidney's headquarters is located in Winston-Salem, North Carolina, a city with a rich history in tobacco and textile manufacturing. Just as Winston-Salem transformed itself from a manufacturing hub to a center for healthcare and innovation, could ProKidney be on the verge of a similar transformation in the CKD landscape?"