Star 3 – The Real Winner is CGM

Star 3 – The Real Winner is CGM

While the folks at Medtronic (NYSE:MDT) believe the results of Star 3 clearly show the benefits of insulin pump therapy or more accurately sensor augmented insulin pump therapy, Diabetic Investor believes the clear winner from Star 3 was continuous glucose monitoring. Here’s why:

First take a look at the way patients were treated. According to the recently published study in the New England Journal of Medicine the patients on pump therapy used the MiniMed Paradigm REAL-Time system which integrates an insulin pump with a continuous glucose monitor. The patients in the injection therapy group used the Guardian REAL-Time clinical which collects but does not display continuous glucose readings to the patient. The Guardian basically provides a retrospective look while the Paradigm REAL-Time provides more of a prospective look. Put more simply patients who can see their glucose trend lines can more quickly adjust their insulin dosing regimen than patients who must wait for data.

Although there is no way to prove this but with yet another study, Diabetic Investor strongly believes that had the patients assigned to multiple daily injection therapy had real time access to their glucose readings this group would have seen better results. That is the whole point of having a CGM, the ability to make therapy adjustments. Does it make any sense to make a patient wait until they see their physician to make therapy adjustments? This may be true with non-insulin using patients or patients who insulin plus orals, however patients on MDI therapy typically are better educated just by the nature of MDI therapy and therefore should be able to make adjustments if given the proper data set.

In the real world the choice between insulin pump therapy and MDI is not based on outcomes. In the real world a patient can achieve just as good outcomes with MDI as they can with insulin pump therapy. The fact is in the real world insulin pump therapy is more a lifestyle choice.  The reality is there are patients who just aren’t comfortable being attached to machine. Additionally insulin pump therapy, even when used in conjunction with a CGM requires more intensive training than MDI therapy. As Diabetic Investor has pointed out in the past this has always been one of the biggest roadblocks to more patients using an insulin pump, they simply do not want to spend hours learning how to pump. This is the same reason more physicians do not recommend insulin pump therapy, it’s easier to train patients on injection therapy than pump therapy.

Looking over the results of Star 3 it’s hard to be impressed with the results. After 1 year patients assigned to the insulin pump group experienced a reduction of 0.8% in HbA1c while the MDI patients experienced 0.2% reduction. Starting from a baseline HbA1c of 8.3% just 27% of the patients in the insulin pump group reached an HbA1c of 7% or below and only 10% in the MDI reached this level. One could argue that with all the information, education and support received by the insulin pump patients that the HbA1c results were actually disappointing.

Also overlooked were the rates of severe hypoglycemia and diabetic ketoacidosis which according to the authors of the study; “were similar in the two study groups”. What does this say about Medtronic’s claim that their sensor is more accurate at detecting hypoglycemia? Would it not stand to reason that armed with the real time glucose data that patients in the insulin pump group would experience significantly fewer hypoglycemic events than those on MDI who did not have real time access to their glucose readings. Or should we interrupt from this data that conventional glucose monitoring is good enough to protect against hypoglycemic events?

The truth is that CGM was the real winner with Star 3 as this study clearly demonstrates the value CGM brings to the intensive insulin patients and it really doesn’t matter whether that patient uses a pump or injects their insulin. A more interesting study would have been to put both groups on real time CGM and see which had better outcomes, but that would have defeated the whole purpose of this study which in reality was for Medtronic to show their integrated insulin pump system is superior to other non-integrated insulin pumps. To Diabetic Investor this is meaningless as Dexcom (NASDAQ:DXCM) has already submitted their application to integrate with the OmniPod from Insulet (NASDAQ:PODD) and they will soon integrate with Animas pumps as well.  As Diabetic Investor has stated before integrated systems will soon become the norm for insulin pumps.

The reality is the insulin pump market is following the same path as the blood glucose monitoring market where all the systems are beginning to look like mirror imagines of each other. The fact is all insulin pumps do exactly the same thing and which pump a patient chooses really gets down to personal preference.  Younger pumpers seem to prefer the Animas line with its larger color screen and many patient friendly features, while MDI patients converting to pump therapy seem to prefer the OmniPod and being wireless. Older more established pumpers remain loyal to Medtronic preferring not to learn a new system when the one they have works just fine. The fact is once CGM is fully integrated with all pumps this situation likely won’t change.

The bottom line here is Star 3 is really more about the benefits of CGM than how insulin is delivered and when it comes to CGM Diabetic Investor sees Dexcom leading the way. The fact is Medtronic may have 65% of the insulin pump market but the Dexcom system has the flexibility to work with patients on intensive insulin therapy whether the insulin is delivered using a pump or multiple injections.