Eli Lilly said on Tuesday it has begun selling vials of the lowest starter dose of its popular weight-loss drug Zepbound in the United States for $399 for a month supply through its direct-to-consumer website to help increase its availability in the marketplace. Zepbound is typically sold in auto-injector pens, but with easier to manufacture and fill vials Lilly will be able to get the drug to patients more quickly. The 2.

5 milligram and 5mg vials -- the lowest doses of the drug -- will cost $399 and $549 on its website LillyDirect, the company said. It has previously said patients could get the drug in a pen through LillyDirect for $550, making the lowest dose now about $150 less per month, a more than 25% discount. Lilly said the prices were in line with its current offering and a 50% discount to the list prices of competing products, including the popular Wegovy from Danish rival Novo Nordisk.

BMO analyst Evan Seigerman said this is likely a new low price for Lilly, even when taking into account after-market discounts the company gives to big health plans. He estimated that those plans receive Zepbound for between $300 and $400 below the more than $1,000 per month list price. He said Lilly was positioning itself against Novo with patients who may eventually get insurance coverage for the drug.

"I think they're trying to really get more people on (Zepbound) at a price that is more affordable," he added. Lilly and Novo have been struggling to produce enough of their obesity .