Express Scripts isn't swayed by Novo's head-to-head Tresiba data

Novo Nordisk ($NVO) has been counting on its new drug Tresiba to carve out a bigger share of the basal insulin market. To help set it apart from Sanofi's ($SNY) long-dominant Lantus--and impending competition from a Lantus biosimilar--Novo cites some trial data showing that Tresiba carries less risk of a much-feared side effect, hypoglycemia.

But according to a top pharmacy benefits manager, that data may not be enough.

Express Scripts ($ESRX) CMO Steve Miller said as much in an interview with Bloomberg. "While I'm not going to tip our hand as to what we're going to do, we find these data important, but not important enough that they will dictate a decision," he said.

Right now, Express Scripts' formulary has Tresiba tagged as "non-preferred," so it carries a higher copay than Lantus. Novo has been working with payers--including Express Scripts--to get the best formulary placement possible for a market-share battle.

The Danish drugmaker has had some success. Using the hypoglycemia advantage and flexible dosing schedule as selling points, Novo has struck a deal with CVS Health ($CVS) for its lowest copay tier for branded meds. Several Humana ($HUM) plans offered the same arrangement. The company is offering copay discount cards to keep patients' share at $15 a month for up to two years, though patients on Medicare or other government programs aren't eligible.

Express Scripts and other PBMs don't much like copay cards because they interfere with efforts to push patients toward drugs where they've negotiated better deals for discounts and rebates.

Express Scripts CMO Steve Miller

Miller told Bloomberg that Express Scripts has developed its own methods for preventing hypoglycemia regardless of which meds a patient is taking. Wi-Fi enabled blood glucose meters, for instance, allow pharmacists to track patients in real time and step in when they see problems, he said.

Novo isn't blind to the pressure from payers--it has conducted multiple studies pitting Tresiba against Lantus to build a case for Tresiba. But Express Scripts may be trying to send a negotiating message to the diabetes-focused drugmaker. Indeed, Miller went on to tell Bloomberg that the PBM is considering an exclusive basal insulin deal, which would award one med a spot on its preferred formulary and freeze the rest out--particularly with Eli Lilly ($LLY) and Boehringer Ingelheim set to launch their Lantus biosim late this year.

That's "always an option," he said, but he also suggested that Express Scripts would see no need for an exclusive deal if it can negotiate good prices with several drugmakers, as it did with the new round of PCSK9 cholesterol meds from Amgen (Repatha) and Sanofi and Regeneron (Praluent).

Analysts are watching the payer talks closely, and keeping an eye on how Novo's data might influence not only payer deals, but doctors' prescribing habits. The hypoglycemia risk data could be enough to boost sales, Bernstein analyst Ronny Gal wrote in a recent investor, particularly before the Lilly/Boehringer biosim launches, but the argument could be tougher after that.

The latest head-to-head trial data "confirms (more thoroughly) the previous observation that Tresiba is better than Lantus on hypoglycemia," Gal wrote. "The question is the clinical relevance of the difference. … Thus, the results are positive, but how positive is yet to be ascertained, in our mind."

- see the Bloomberg interview

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