Comparative Effectiveness and the SATURN study Comparing Crestor with Lipitor
Comparative effectiveness studies like the recently reported SATURN study comparing Crestor® (rosuvastatin) with Lipitor® (atorvastatin) sponsored by AstraZeneca may on the surface appear to be a big win for patients (and prescription drug providers) especially those awaiting generic versions of Lipitor (anticipated by the end of this year). The reported preliminary topline results show a numerical advantage favoring Crestor but no statistically significant difference in the primary endpoint of the study (change from baseline in percent atheroma volume (PAV) in a ≥40 mm segment of the targeted coronary artery as assessed by intravascular ultrasound).
The apparent implication from these results is that there is no difference between Crestor and Lipitor and therefore, when available, generic atorvastatin will work just as well as the brand Crestor. Extrapolating this “no difference” conclusion for a single endpoint to the totality of efficacy for atorvastatin could result in significant cost savings for patients and providers of prescription drug benefits. You would think this is great news for patients but I believe the ramifications of this study go well beyond cholesterol lowering agents and the impact on future sales of Crestor.
Because of the investor interest, high media visibility, the enormous healthcare cost savings potential, and the mass market served by cholesterol lowering agents I believe there will be significant fallout from this study that is not necessarily beneficial to patients.
First, there are undoubtedly going to be patients who could benefit from Crestor rather than atorvastatin but who will not be given that option. Smaller patient populations may never be studied well enough to determine if there really are patients who might benefit from one product or another in the face of large comparative trials showing no statistically significant difference.
Second, company executives have always been, but will now be even more, reluctant to sponsor comparative effectiveness studies for established products even when they feel they have an opportunity to demonstrate a difference (as I believe was the case for AstraZeneca). The requirement for “statistically significant” clinically meaningful differences may be too high a hurdle (and represent too much risk) when complex trial designs are expected to prospectively identify a specific primary endpoint for a patient population with considerable variability. We may, in an ideal world, feel we know enough about biology, disease pathophysiology, pharmacology, and the nuances of patient populations to be able to precisely design these definitive trials, but we probably don’t for most diseases.
Third, pharmaceutical companies may prematurely stop developing drugs they feel might not be able to demonstrate statistically significant differences to available therapeutic agents. This would have been a catastrophe for antivirals HIV/AIDS treatments which we now know work best as cocktails of several products rather than one being “statistically significantly “ better than another. To further complicate this, regulatory approval studies are designed to establish efficacy and safety, not superiority. I believe the need for demonstrating a statistically significant difference to meet market expectations and regulatory requirements for making a superiority claim (or to potentially gain approval) will make drug development near impossible where products already exist and efficacy is well established.
And if you are thinking about developing an as effective but “safer” product, good luck. Regulatory requirements for claiming “safer” are even more challenging and from what I have seen, near impossible.
Lastly, this market expectation for demonstrating “superiority to available treatments” and regulatory requirements for making those claims, I believe will result in fewer therapeutic options for treating specific diseases (think antibiotic drug development over the past decade). We are getting to a point where if a product is already available to treat a disease, clinicians and payers want to know if your new product is better. You would think this is not an unreasonable expectation, but it is an expectation that increases the cost, complexity, and uncertainty of drug development.
At the same time, pharmaceutical companies that demonstrate statistically significant differences for their branded products in comparative effectiveness trials will be able to command “super premium pricing” with an almost monopolistic “treatment of choice” position for the duration of their patent. When a product demonstrates a clear benefit (statistically significant) over other treatments the bar is raised for subsequent new products to demonstrate statistically significant superiority. For products with trial supported superiority, regulators will have no choice but to allow superiority claims, physicians will have little choice but to prescribe the product, and payers will have little choice but to provide reimbursement. Unfortunately, this also dampens drug development interest in therapeutic categories that already have well established “treatments of choice.”
And while we may have more effective and potentially safer products in the future, if you think prescription drug prices are high now, just wait for these products that establish “treatment of choice” with clinically meaningful statistical differences. firstname.lastname@example.org