New Analgesic: Nucynta (tapentadol)

When's the last time you saw a new pain pill? NUCYNTA™ (tapentadol) is a single molecule with a different approach to pain relief. It is the first new molecule in analgesia in over 25 years for the relief of moderate to severe acute pain in adults.

According to a a Phase 3 clinical study published in the June 2009 issue of Current Medical Research and Opinion, tapentadol immediate release (IR) tablets provided patients with equivalent efficacy in pain relief following orthopedic surgery and significant reduction in nausea and/or vomiting compared to oxycodone IR.

NUCYNTA™ combines opioid and nonopioid activity in one centrally acting oral analgesic.

Mu-Opioid Agonist (Ascending Pathways)

• Work primarily on ascending pathways to inhibit transmission of pain impulses through binding to mu-opioid receptors
  

Norepinephrine Reuptake Inhibitor (Descending Pathways)

• Norepinephrine reuptake inhibition works primarily on the descending pathways to enhance the inhibition of pain signaling
  

However, the exact mechanism of action of NUCYNTA™ is unknown. Isn't it interesting that we use so many medications that have an unknown mechanism of action? People may ask, "how does it work?" Answer: I don't know, but I know it works. To stay consistent with the "pain theme," let's talk about Lyrica (or pregabalin). This snippet is straight from the product insert: "LYRICA (pregabalin) binds with high affinity to the alpha2-delta site (an auxiliary subunit of voltage-gated calcium channels) in central nervous system tissues. Although the mechanism of action of pregabalin is unknown, results with genetically modified mice and with compounds structurally related to pregabalin (such as gabapentin) suggest that binding to the alpha2-delta subunit may be involved in pregabalin's antinociceptive and antiseizure effects in animal models." Lyrica is made by Pfizer.

There's simply so much we don't understand about pain. It's interesting to see research being done on drugs that have mysterious and unknown mechanisms of actions. We can postulate and theorize, but we can't prove how they work yet.

If you wish to learn more about Nucynta, visit: http://www.nucynta.com
Nucynta is marketed by Ortho-McNeil-Janssen Pharmaceuticals, Inc.

Rivaroxaban to be Reviewed by the FDA Panel on March 19

March 19 is match day for 4th year medical students. It's also the day when the FDA Panel is supposed to review the anticoagulant rivaroxaban (also known as BAY 59-7939 or Xarelto). It is an oral, direct Factor Xa inhibitor (I don't think I'll ever forget that coagulation cascade diagram that I learned in medical school). If approved, this drug could shut down all those coumadin (warfarin) clinics out there that monitor blood INR in people taking this vitamin K antagonist. Rivaroxaban would not require any blood monitoring. Plus, all those home INR tests manufacturers would need to look for something new to do.

I think everyone is wondering how the FDA will react to this new medication. If approved by the FDA, rivaroxaban will be sold in the US for short-term use as a prophylactic anticoagulant for patients undergoing knee- and hip-replacement surgeries. I'm sure the drug manufacturers will go for additional indications later on. Rivaroxaban is manufactured by Bayer and will be marketed by Ortho-McNeil Pharmaceutical which is a Johnson & Johnson group.