WASHINGTON (AP) — Approvals for first-of-a-kind drugs climbed last year, pushing the annual tally of new U.S. drugs to its highest level in 19 years.

The rising figures reflect an industry-wide focus on drugs for rare and hard-to-treat diseases, which often come with streamlined reviews, extra patent protections and higher price tags.

The Food and Drug Administration approved 45 drugs with never-before-sold ingredients in 2015, edging past the previous year's tally of 41, which had been the highest number since 1996.

FDA drug approvals are considered a barometer of industry innovation and the government's efficiency in reviewing new therapies.

While the trend toward specialty medicines is good news for industry and patients, it is likely to stir debate about rising prescription drug prices. That issue has become a top concern for consumers, a subject of congressional scrutiny and even an issue on the presidential campaign trail. Democratic candidates Hillary Clinton and Bernie Sanders have both outlined proposals designed to curb prices.

The FDA is not allowed to consider prices when approving medicines, though some experts argue it should.

One of the most expensive drugs of the year was Vertex Pharmaceuticals' Orkambi for cystic fibrosis, priced at $259,000 for a year's supply. The drug improves lung function in patients with the deadly inheritable disease, which causes the buildup of sticky mucus throughout the body. Pfizer's breast cancer drug, Ibrance, was priced at $118,200 per year, which was typical of new cancer drugs. Even some drugs for more prevalent diseases came with high price-tags: Bristol-Myers Squibb's hepatitis C pill, Daklinza, costs $63,000 for a 12-week regimen.