The key question going into the ADA meeting is what doctors think about the data, especially on weight loss, said Mark Schoenebaum, an analyst with ISI Group. He expects Lilly's drug to still gain significant market share in its class of medicines, called GLP-1s, noting they make up a $3 billion market that could grow to $5 billion "in the out years."
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"It's quite possible that even a 33 percent penetration rate is possible here (implying $1.7 billion in peak sales) given it has, on the overall, a competitive profile vs. Victoza," Schoenebaum wrote in a June 9 research note of Lilly's dulaglutide.
Finally, Lilly also will have data on a combination of drugs called empagliflozin and Tradjenta in an increasingly competitive area. AstraZeneca is presenting data on a similar combination of drugs, and Holford said he expects both to reach the market in 2015.
Which brings us to: