Human Genome Sciences collected $7.8 million from sales of its lupus drug Benlysta during its first three months on the market, a figure executives said should continue to climb as physicians become more comfortable with the product.

Executives told investors Thursday that more physicians than expected are aware of the drug and soon plan to prescribe it, but some remain cautious about which patients are eligible and how they’ll be reimbursed financially.

“This remaining caution. . .can only be fully addressed by experience,” Barry Labinger, executive vice president and chief commercial officer, said during a conference call. “We are seeing a positive reception from our customers and the challenges we’ve encountered are entirely expected.”

Indeed, the Rockville company said net sales per week from Benlysta increased for each of the three months in the second quarter, and they anticipate it will continue to grow as physicans become more comfortable.

The first month saw net sales of $270,000 per week, which grew to $630,000 per week for the second month and $1.05 million per week for the third, said David Southwell, executive vice president and chief financial officer.

“We are seeing a nice growth trajectory in Benlysta sales and we’re especially pleased the fundamentals are lining up nicely to drive continued growth in the future,” Labinger said.

The update came as part of the company’s second-quarter earnings call with investors and marks the first time executives have discussed Benlysta’s sales figures since the Food and Drug Administration approved the drug in March.

The company reported revenue of $24.9 million for the three months ending June 30, a 35.8 percent decline from the same period last year. The result was a net loss of $80.7 million, or 42 cents a share, for the quarter.

Wall Street analysts polled by Thomson Reuters predicted, on average, a net loss of 42 cents a share, but pegged the company’s second-quarter revenue to come in at $28.65 million.

The earnings were dragged down in part by $19.1 million in upfront and milestone payments that HGS no longer receives for the development of Zalbin, the hepatitis C drug that it and partner Novartis abandoned last October.

Benlysta, which is co-developed with GlaxoSmithKline, is the first drug for HGS on the commercial market.

The company already had begun to hire and train a national sales force at the end of last year in anticipation of approval after a FDA advisory panel recommended last November that the agency green light the drug.

Executives said at the time there would be a short turnaround time between Benlysta’s approval and when representatives would knock on physician’s doors. The original decision deadline was set for Dec. 9, but a postponement by regulators left even more time to prepare.

Executives said the company will continue to expand in the United States, but now has its eye on foreign markets. In recent weeks Benlysta won approval from European and Canadian health agencies and applications have been submitted to regulators in Australia, Russia and Brazil, among other countries.