Titan Pharmaceuticals Inc (TTNP)

[Doctor Detroit]

WHO KILLED PRINCE? RESTRICTIONS ON BUPRENORPHINE

https://jebkinnison.com/2016/05/17/who-killed-prince-restrictions-on-buprenorphine/

The title is a little questionable, but an interesting take on the history of probuphine in this blog

Thus the need for a drug delivery system that didn’t allow for easy diversion or abuse, and delivered a constant dose of the medication without requiring the patient to remember to take it. Titan Pharmaceutical’s Probuphine, an implantable form of buprenorphine, started development in 2000, was rejected by the FDA in April 2013 for what appear to be murky reasons, and is up for approval again in 2016 after a three-year delay to gather more data to answer FDA questions. The episode looks like an instance of Bootleggers and Baptists overregulation, with vested interests blocking a much-needed new drug implant to protect their interests while throwing up a cloud of “concerns” to justify their actions.

Titan began development of the drug implant in 2000 after licensing the patent from MIT in 1996. At the beginning of development, buprenorphine was approved and in use for anti-addiction treatment in France and Australia, but was awaiting more studies and FDA approval in the US. When the FDA approved buprenorphine tablets in 2002 under the then-new law allowing opioids to be prescribed for addiction treatment, Titan appeared to have a winning idea on its hands after the DEA and FDA soured on the bright early hopes for tablet-delivered buprenorphine — Titan’s implantable form would address all of the issues that so concerned the DEA and improve success rates among addict populations.

But the FDA rejected Titan’s application in April of 2013 despite the positive recommendation of their panel of outside medical experts, a rare event. The company’s stock dropped by 80%, typical when a small drug company’s key development project is rejected. One biotech publication outlined the FDA’s position:

In the end, a vote by an outside panel of FDA experts favoring approval of Titan Pharmaceuticals’ Probuphine didn’t influence the outcome at all. Agency staffers stuck with the opinions outlined in a harsh internal review and rejected the opioid addiction drug, outlining some extensive demands for new clinical data that would be needed for an approval.

In a statement, Titan ($TTNP) outlined three key requirements on new efficacy data. Titan will have to offer clear evidence of:

• The ability of Probuphine to provide opioid blockade of relevant doses of agonists.
• The effect of higher doses of Probuphine, ideally doses more closely approximating the blood plasma levels associated with sublingual doses of buprenorphine of 12 to 16 mg/day.
• Human factors testing of the training associated with Probuphine’s insertion and removal.

The FDA’s panel had voted 10 to four in favor of an approval, but the agency had no problem overlooking the majority support along with Titan’s claim that Phase III data demonstrated that Probuphine, an implant that releases buprenorphine over a period of 6 months, was better than a placebo at preventing addicts from using illicit opioids. Investigators also said it was noninferior to the approved therapy. But staffers picked apart that argument in the internal review.[8]

The outside panel recognized that while results were not perfect, Titan’s product was needed immediately and offered enough advantages over alternatives to merit approval. FDA staff decided to reject the drug and require several more years of studies and delays before looking at it again.

Remember, this is a widely-used drug since 2002, and the company had been at work on the required studies for many years before bringing it to the FDA for approval in 2013. The delay nearly killed the company and the implant product, and Titan was forced to sell rights to the drug to another company, Braeburn Pharmaceuticals, to get enough money to continue.

Because the FDA is an unelected, unaccountable bureaucracy, no one knows how often their decisions are swayed by politics and under-the-table influence-peddling. Doctors can be stubborn and view themselves as protecting the public, or require even more proof of efficacy, or perhaps can be influenced by communications from Big Pharma interests who might see opioid revenues decline if better treatments for opioid addiction became available. No one knows or can know whether improper influence occurred in this case — it’s best to assume erroneous belief, rather than corruption, causes this kind of damaging mistake.

Titan came back to the FDA with the requested new studies, and a hearing was held January 13, 2016. The Psychopharmacologic Drugs Advisory Committee again has recommended approval, this time by a vote of 12-5. But again, some panelists were against approval, working hard to come up with reasons to deny a new treatment to people with life-threatening addictions:

Probuphine works like a contraceptive implant, such as Norplant. Four implanted rods, each smaller than a matchstick, provide a steady amount of medication for up to 6 months. The FDA is considering approving it for a specific population: “stable” patients who are already taking the dissolvable buprenorphine film at a low dose. The committee voted 12-5 in favor of probuphine.

“I think this will save some folks’ lives,” said advisory committee member David Pickar, an adjunct professor of psychiatry at Johns Hopkins Medical School in Baltimore.

Doctors who want to prescribe probuphine would have to refer patients to providers trained to implant medical devices, or undergo training to learn how to safely implant and remove it, said Behshad Sheldon, president and CEO of Braeburn Pharmaceuticals, who spoke at Tuesday’s advisory committee hearing.

Implanting probuphine takes 10 to 15 minutes and removing it takes about 20 minutes, said Steven Chavoustie, a physician involved in a clinical trial of the device.

Pharmacist Tracy Rupp urged the committee to reject probuphine, noting that its manufacturer presented only one clinical study showing the drug was effective.

In the study, doctors compared the use of probuphine implants and buprenorphine film, Sheldon said. Patients in the study were considered “stable” because they had been safely using the films. After 6 months, 85% of those given probuphine tested negative for illegal drugs, compared to 72% of those given the film.

The study had multiple flaws, said Rupp, director of public health policy initiatives at the National Center for Health Research, a nonpartisan group that analyzes health data.

Some missing urine tests were counted as negative, as if the patient had no drugs in their system. But Rupp noted that people addicted to opiates “often skip tests to avoid a positive test.” That could skew the results, Rupp said.

“It is disappointing that the advisory committee set such a low bar for safety and effectiveness,” Rupp said after the vote. “Is probuphine effective? We still don’t know because the study was poorly designed and missing data.”

Judith Kramer, the committee’s acting chairwoman, said she voted against recommending probuphine’s approval because doctors don’t yet know if it’s effective for more than 6 months. Many people who are addicted to opiates need to take medication for years, she added.[9]

Notice the proposed use is now restricted to patients already on the film form of the drug, and the advantages—six months guaranteed compliance, for example—are ignored in favor of nitpicking, as if the efficacy of the drug itself has to be proven all over again. The goalposts have been moved. The FDA will rule soon, and may well reject the drug again despite the positive panel recommendation.