Can Botox hang with CGRP in migraine? Allergan says yes; analysts are skeptical

Allergan CEO Brent Saunders says Botox is holding its own against tough new rivals. (Allergan)

Last week, Allergan CEO Brent Saunders told investors that Botox “continues to remain very strong” in migraine despite the arrival of three drugs from the brand-new CGRP class. But exactly how strong?

As company executives told analysts at Bernstein, the new-to-brand share for Botox in migraine equals that of the group of newcomers, which comprises Amgen and Novartis’ Aimovig, Teva’s Ajovy and Eli Lilly’s Emgality.

Don’t believe it? Neither did the analysts. The stat “sounded odd,” Bernstein’s Ronny Gal wrote in a note to clients, so he and his colleagues asked Allergan to confirm—and it did.

"In terms of new to brand, what we have seen so far is that it is a 50/50 split between Botox and the CGRP mAbs. So mathematically, based on data in recent weeks, more patients are starting Botox than Aimovig,” the company said, adding that “~6% of patients on Aimovig are also receiving Botox."

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Nevertheless, the way Gal sees it, it still “seems unlikely that Botox is adding patients as fast as the new class,” he wrote. But if patients hearing about CGRP are going to their doctors and asking about their options—and then choosing Botox from that list—“it would be a significant upside to Botox expectations in 2019.”

Investors haven’t been so hot on Botox’s prospects over the last year-plus, which is one reason Allergan's shares have languished. A year ago, Bernstein polled 100 high-volume U.S. aesthetic physicians to find that they expected forthcoming head-to-head Botox competitors from Revance, Evolus and Hugel to snatch up to 33% to 34% of the aesthetics market.

RELATED: Look out, Allergan: Doctor surveys show the 'Botox competitive threat is real'

That potential rivalry makes Botox’s medical indications all the more critical for Allergan, but the CGRP class is expected to give it a major run for its money. As Amgen CEO Robert Bradway said last week at the J.P. Morgan Healthcare Conference, 150,000 patients have already started on Aimovig.