When OxyContin hit pharmacies 20 years ago, its primary selling point was that a single dose of the opioid pain medication lasted 12 hours, “providing smooth and sustained pain control all day and all night,” per the press release. But a new report claims Purdue Pharma, the makers of OxyContin, have long known that the drug doesn’t always live up to this promise, resulting in an increased likelihood for abuse and addiction.

An in-depth review of internal and court documents by the L.A. Times turned up evidence that Purdue became aware during the clinical trial phase — long before OxyContin hit the market — that some patients were not getting the promised long-term pain relief from the medication.

In fact, seven years before the drug’s release, OxyContin was tested on 90 women — none of them regular users of painkillers — recovering from abdominal and gynecological surgery. According to the Times, more than one-third of these women complained about their pain returning within eight hours, and around half of them said their pain had come back before the full 12 hours.

A later trial on cancer patients had to be redesigned after a large number of test subjects dropped out because they found OxyContin to be ineffective in managing their pain. The rejiggered study allowed patients to take supplemental “rescue” medication in-between their doses of OxyContin. Yet another study using cancer patients found that 95% of those in the test group had resorted to taking a secondary painkiller at some point during the trial.

The FDA standard only required that Purdue could demonstrate that the drug was effective for 12 hours in at least half the patients, meaning that it was within tolerable limits for one-third of patients to not see that level of relief.

For what it’s worth, the FDA official who led the review — and subsequent approval — of OxyContin went to work for Purdue after leaving the agency not long after the drug’s 1996 release.

Purdue never tested the drug at intervals shorter than 12-hours and, in spite of the fact that a substantial portion of patients had not seen the full half-day of pain relief, the company chose to make this 12-hour feature the core of its marketing.

It continued to do so even after patients and doctors began reporting back that the drug did not always last as long as it needed to.

When some doctors began instructing patients to take OxyContin more frequently, the Times reports that Purdue responded by urging these physicians to instead prescribe higher doses.

Even as some doctors were complaining that upwards of 80% of their patients were only seeing 4-8 hours of relief from OxyContin, sales reps were told to convince these physicians to stick to the 12-hour guidelines because testing had shown that “100% of the patients in the studies had pain relief on a q12h dosing regimen.”

The reps were also reminded that they could encourage doctors to increase the amount of OxyContin prescribed every 12 hours because there was no upper limit on that number.

But, as the Times points out, a boost in dosage primarily benefits Purdue’s bottom line, as a bottle of 10mg OxyContin bills brought in $97 for the company in 2001, compared to $630 a bottle for the 80mg version of the drug.

Sales reps were told that, by encouraging doctors to sell the larger doses, they could “blow the lid off” their sales stats and earn bonuses, like a trip to Hawaii

Within five years of its release, OxyContin was bringing in $1 billion a year in revenue. By 2010, that number grew to $3 billion, accounting for one-third of all sales revenue from painkillers.

For more on Purdue’s addiction to 12-hour OxyContin, check out the full L.A. Times report.

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