In 2013, painful diabetic neuropathy (PDN) affected more than 3.4 million people in the United States. Similar to postherpetic neuralgia, PDN has also served—and continues to serve—as a gateway indication into the broader neuropathic pain (NP) market because, according to experts interviewed by Decision Resources Group, PDN patients are generally easy to recruit for clinical trials, are fairly homogenous (i.e., they often do not suffer from forms of pain with mixed neuropathic/inflammatory components), and are reasonably responsive to treatment compared with other NP populations. Nevertheless, the entrenchment of relatively inexpensive early-line therapies prescribed for PDN (e.g., gabapentin [Pfizer’s Neurontin, generics]) makes penetrating this market difficult.
Importantly, the treatment guidelines published in 2011 for PDN by the American Academy of Neurology, the American Association of Neuromuscular and Electrodiagnostic Medicine, and the American Academy of Physical Medicine and Rehabilitation indicate a Level A (strong evidence) recommendation for pregabalin (Pfizer’s Lyrica) only and a Level B (moderate evidence) recommendation for a variety of other analgesic agents, including gabapentin, amitriptyline (generics), duloxetine (Eli Lilly’s Cymbalta, generics), tramadol (Janssen’s Ultram/Ultram ER, other brands, generics), and opioid analgesics. Using national patient-level claims data, this report analyzes physician adherence to the treatment guidelines by exploring the use of key therapies (including brand-only therapies, such as Lyrica) in the newly diagnosed and recently treated PDN patient populations. Among the newly diagnosed patients, the report provides a quantitative analysis of treatment patterns and share by line of therapy, as well as progression between lines, duration of treatment on each line, and use of concomitant treatment. Among recently treated patients, the report quantifies a drug’s source of business compared with its competitors and details which drugs precede others through an analysis of add-versus-switch patterns. Additional analyses explore persistency and compliance by brand.