This story has been updated. 

When Sanofi’s multiple sclerosis drug Aubagio came to market in 2012, it did so under circumstances that were less than ideal.

It was the second disease-modifying therapy for MS to arrive on the scene — Novartis’ Gilenya, another oral DMT, had already been approved — while Biogen was closing in on approval for Tecfidera, which was heralded as a potential blockbuster.

Fast forward to 2017, during which Aubagio is expected to enjoy a robust 21% jump in sales vis-à-vis 2016 — from $1 billion to $1.2 billion, EvaluatePharma reports.

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That surge bestows upon Aubagio the distinction of most switched-to oral multiple sclerosis drug.

So what’s the secret behind its slow-building success?

According to Christina Rossi, North American commercial lead for multiple sclerosis at Sanofi Genzyme, team Aubagio overcame its initial challenges by leveraging real-world data and investing in two additional Phase-III studies that further demonstrated its efficacy.

MOUNTING A COMEBACK

It wasn’t an easy fix, especially given the relatively unenthusiastic response Aubagio received at launch.

“There wasn’t a lot of experience with the drug product prior to launch, and it didn’t have the most favorable impressions coming in. In addition, we were facing the approval and launch of Tecfidera,” Rossi explains.

Tecfidera’s looming threat may have been the most imposing obstacle. In 2013, one analyst, Evercore ISI’s Mark Schoenebaum, said the drug projected as “the holy mother of all launches.”

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Early on, Tecfidera consistently beat even the rosiest sales forecasts and almost singlehandedly grew the market for oral MS therapies.

Aubagio began mounting a comeback in 2014, when Sanofi added the results from two new Phase III trials, TOWER and TOPIC, to the drug’s label. Rossi believes the moves helped drive adoption.

“They allowed us to distinguish Aubagio as the only oral therapy that has demonstrated significant impacts on disability progression in two separate Phase III studies, which has been an important piece of data for prescribers,” she explains.

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Bill Sibold, EVP and head of Sanofi Genzyme, agrees. During the company’s Q2 earnings call, he attributed Aubagio’s increased sales to the “real-world profile that physicians are seeing.”

The uniqueness of the MS space played a part, as well. Unlike in many other specialty drug categories, switching therapies is not uncommon in the treatment of MS.

“MS is a lifelong disease, and patients need to be managed over a long period of time. One thing that has changed in this space is there are a lot more options,” Rossi notes.

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“When I first started working in MS, there were only injectables, and there were four of them. Now there are orals and infusion options. These products have different efficacy and safety profiles. There’s less tolerance for disease activity if someone is on therapy.”

Tolerability, the measure of whether a patient can bear a drug’s adverse effects, may have also helped drive Aubagio adoption. Tecfidera has faced tolerability setbacks, due to a few cases of a rare brain infection known as progressive multifocal leukoencephalopathy (PML) in patients taking the drug.

The FDA first sounded a warning about Tecfidera in 2014, adding to the drug’s label that an MS patient who was treated with the drug developed the rare brain infection and died.

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Through September, there have been four cases of PML reported among patients taking Tecfidera.

Still, Rossi counters that Sanofi began seeing a trend toward Aubagio adoption before PML made headlines. “This is a very safety-focused market in general, [but] we started to see accelerated adoption with Aubagio prior to some of the PML issues that came up with Tecfidera,” she says.

“Sometimes the narrative is that it’s always about PML, but a lot of it is really about the clinical experience people have with [Aubagio] and its strong efficacy.”