Drs. Anish Kirpalani and Darren Yuen, both of St. Michael's Hospital in Toronto, appear to be on the verge of a major practice-changing advance in the assessment of chronic kidney disease. Their study, appearing in cJASN, describes the new methodology which assesses kidney fibrosis in a novel way using MRI. We caught up with the authors of this exciting study and they shared some further perspective on their exciting findings.
UKidney Nephrology News and Insights
Topline results of the Reprise Study in ADPKD have been announced and the good news continues for ADPKD. According to top-line results released by Otsuka, the maker of Tolvaptan:- Primary and key secondary endpoints were positive for tolvaptan vs. placebo in an additional Phase 3 clinical trial that examined the efficacy and safety of tolvaptan in autosomal dominant polycystic kidney disease (ADPKD)- The data are intended to address the Complete Response Letter (CRL) issued by the FDA for a New Drug Application (NDA) for tolvaptan in ADPKD in 2013- Trial results will be submitted for presentation at a nephrology medical congress in the second half of 2017
A long awaited analysis of the renal outcomes from the EMPA-REG study was published in the New England Journal of Medicine on June 14th . As originally reported on UKidney, compared to patients taking placebo, the use of empagliflozin was associated with significant improvements in important renal end-points, namely doubling of serum creatinine and end-stage renal disease (ESRD). While these results are indeed very promising, some perspective is warranted when considering the potential nephroprotective properties of this drug, and of the SGLT2 inhibitor class in general.
The SPRINT Study was received with great fanfare when it was published on November 26th in the New England Journal of Medicine. The primary results, summarized in the publication’s abstract are these:
"Among patients at high risk for cardiovascular events but without diabetes, targeting a systolic blood pressure of less than 120 mm Hg, as compared with less than 140 mm Hg, resulted in lower rates of fatal and nonfatal major cardiovascular events and death from any cause, although significantly higher rates of some adverse events were observed in the intensive-treatment group."
The essential word in that abstract’s conclusion - and which prevents the application of these results - is ‘targeting’. The conclusion accepted by many is that aggressive blood pressure reduction, that is the achieved blood pressure, drove the observed results. However, it may well be that the act of targeting a low blood pressure, and using cardioprotective drugs to do so, explained the results rather than the reduction of blood pressure itself. And unravelling this nuance is the key to understanding whether SPRINT’s main message is applicable to the general population. I would argue that in its current form SPRINT suffers from a major methodological short-coming that leaves us in a quagmire.
As we continue to process data from the EMPA-REG renal outcomes presentation - which most importantly showed a 46% reduction in the composite of creatinine doubling, end-stage renal disease or renal death - speculation is well underway to explain the mechanism for renal protection. And the emerging story appears to be quite fascinating indeed.
Data from the EMPA-REG study were unveiled in Stockholm 6 weeks ago. In more than 7,000 adults with type 2 diabetes (T2D) at high risk for CV events, EMPA-REG OUTCOME met its primary endpoint and demonstrated superiority of JARDIANCE, when added to standard of care, in CV risk reduction. The primary endpoint was defined as time to first occurrence of either CV death, or non-fatal myocardial infarction or non-fatal stroke.
Canada becomes the first country outside Japan to approve JinarcTM (Tolvaptan) for the treatment of ADPKD. This medication, dosed twice daily, is the first of its kind to show a slowing in renal function decline as well as a slowing in kidney enlargement among patients with ADPKD.
Previously, UKidney News reported a possible link between calcium channel blockers and the development of breast cancer. Data from the Intermountain Medical Center Heart Institute study were presented at the 2014 American Heart Association Scientific Sessions in Chicago, dispelling some of this concern:
"We found no robust data that calcium channel blocker medications increase a person's risk of breast cancer," said Jeffery L. Anderson, MD, a cardiologist and researcher at the Intermountain Medical Center Heart Institute. "Given the important role calcium channel blocker medications play in treating heart conditions, we think it's premature to discontinue their use. At this point we recommend that patients continue taking these medications to treat their hypertension."
While it is very difficult to ever prove a negative association, these data do provide some reassurance to a large number of patients using this important antihypertensive.
Imagining the Dream RCT in nephrology is an important exercise, but not for the reasons you might think. For many, there might be the temptation to devise trials that will pave the way for future enhancements to patient care or to some other exciting, forward thinking outcome. For me however, the Dream RCT in nephrology is about shattering or affirming nephrology dogma - and in nephrology we seem to have more dogma influencing core tenets of our specialty than in other medical disciplines. There is a popular saying among those in the clinical epidemiology world - that you don’t need to conduct an RCT to prove that parachutes are required when jumping out of a plane. Unfortunately in nephrology, thought leaders have bestowed parachute status on too many interventions. I can think of no better example for this analogy than treating hyperphosphatemia in CKD/ESRD. And it is this topic that would underlie my Dream RCT.
Top-line results of the Symplicity 3 trial were revealed this week, showing that despite being safe, renal denervation was no better than a sham procedure at controlling blood pressure at 6 months. As reported on Medscape: