More prescription drug prices fell in the third quarter of 2019 than rose, according to a review of data collected by the U.S. Centers for Medicare and Medicaid Services.

The average per-unit price for Sanofi's rapid-acting insulin medication Admelog decreased by 44% in July, the National Average Drug Acquisition Cost survey showed. Admelog was launched in 2018 as a biosimilar to Eli Lilly and Co.'s Humalog medication. The per-unit price for Admelog on the Sept. 25 report was $16.20 for the SoloStar pen and $12.57 for the 100-milliliter vial.

Policy makers have sought to incentivize the development of cheaper, biosimilar insulins in response to public concern about rising drug costs. Insulins have come under particular scrutiny in Washington.

In aggregate, the average per-unit price retail pharmacies pay for 1,330 generic medicines were lower at the end of September when compared to the average per-unit price on June 26, while 867 medicines saw a price increase.

The largest reported decrease of an individual medication was a 5-milligram dosage of the opioid pain medication, oxycodone hydrochloride. The average per-unit price of the capsule decreased to 27 cents in September, which was roughly 63% lower than the price listed on the June 26 weekly NADAC report.

The biggest reported increase for an individual medication over the past several months is promethazine dextromethorphan, a medicine that treats symptoms caused by the common cold and allergies. Retail pharmacies will now pay a modest per-unit price of 3 cents per milliliter, a jump of 161.9%.

The NADAC survey tracks what retail community pharmacies pay for outpatient prescription and over-the-counter medicines covered by Medicaid, the U.S. health insurance program for low-income Americans.