UPDATED: Goldman cuts Afrezza sales forecast in half on slow uptake, pricing pressure

Pharma watchers have been tracking the launch of MannKind's ($MNKD) Afrezza like other people track batting averages or Oscar buzz. Unfortunately for fans of the inhaled insulin, early numbers don't look good. So much so that Goldman Sachs ($GS) downgraded MannKind's stock and cut its peak sales projection in half.

The problem isn't just with sales numbers for the drug's first few weeks on the market, though those are less than impressive. Goldman says script numbers are falling "far short" of the firm's expectations. It accompanied that statement with a chart that depicts the firm's forecast rising at about a 30-degree angle--and actual scripts barely above horizontal.

Sanofi ($SNY), MannKind's marketing partner, can't be happy with a slow start, but as the company points out, it's early days. "As it has only been one month since our official U.S. launch of Afrezza, the data available is limited," the company said in an emailed statement. So far, the drug has been "well received" by healthcare pros and patients, the company says, and "we are encouraged by this early feedback."

After all, the Afrezza launch comes with the particular challenge of persuading doctors and patients that inhaled insulin can work as well as the injectables they're so familiar with. But put that particular marketing hurdle in a vacuum, and the progress might be more impressive. The other problem Sanofi and MannKind face, Goldman's Jay Olson points out, is the overall pressure on the diabetes market.

"Diabetes market dynamics have deteriorated as reflected by growing pressure on prices and slow launch uptakes," Olson wrote in a note to investors, adding that both have been "unfavorably influenced" as payers leverage their formulary-selection power to wring cost concessions from companies.

In Sanofi's case, those discounts might have to run up to 40% off Afrezza's sticker price, Olson says. That's higher than Goldman--or any analyst, for that matter--had predicted ahead of time. Goldman now figures on $1 billion in peak sales for Afrezza, rather than the $2 billion it previously predicted.

Goldman has been on the high side of those predictions. Morningstar's forecast was $2 billion at launch time, with Thomson Reuters at $182 million on the low end, and most of the rest around $600 million or so.

Meanwhile, Sanofi will keep on keeping on, with doctors and payers alike. "Our field force is executing according to plan," the company said, "and we are focused on introducing Afrezza to healthcare professionals and working with insurance plans to speed their formal reviews of Afrezza." Any hard data on the fruits of those labors--dollarwise--will have to wait till quarterly financials come in.

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Editor's note: This story was updated with comments from Sanofi.