California legislators have passed a bill aimed at creating greater transparency around prescription drug pricing by requiring pharmaceutical manufacturers to provide advance notice and more detailed explanations for raising the price of a drug. The legislation, SB 17, was approved by the Senate on Wednesday after clearing the Assembly earlier this week. The proposal now heads to Gov. Jerry Brown. Under the measure, drug companies would have to alert health insurers at least 60 days before they plan to increase the price of a drug if the increase is at least 16% over a 2-year period. The requirement would apply to drugs that have a wholesale price of least $40 for a course of therapy. Drug companies would have to provide an explanation for the price increase. The bill would also require health insurers to report to the state details about their spending on prescription drugs, including a list of the 25 most frequently prescribed drugs, the 25 costliest drugs by annual spending, and the 25 drugs with the highest year-over-year increase in total annual spending. The bill was opposed by Pharmaceutical Research and Manufacturers of America, which warned that consumers would not see meaningful improvements on affordability, and instead "mounds of red tape and government reports (would be created) that look only at the list price of a prescription drug rather than considering actual patient spending after negotiated discounts and rebates."