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.
Questions Answered in This Report:
- Newly diagnosed patients: A little more than one-third (35.2%) of newly diagnosed PDN patients began treatment with a key therapy within one year of their initial diagnosis. What percentage of these patients progress to a second- or third-line drug within the first year? Which products capture the most patient share in the first, second, and third lines of treatment? How often is combination therapy used in each line of therapy?
- Recently treated patients: Three distinct classes of agents captured sizable share among recently treated PDN patients: antiepileptic drugs, opioid analgesics, and antidepressants. Which specific drugs garner the most patient share for recently treated PDN patients? When do patients progress from one therapy to the next in PDN, and how does this pattern differ among key drugs? Are most recently treated patients for each key brand coming from new (adds/switches) or continuing business?
- Pathways to key therapies: Longitudinal claims data reveal relatively consistent use patterns of key therapies among recently treated PDN patients; because no single PDN therapy provides more than partial analgesia, PDN treatment is characterized by a high rate of switching from one agent to another. Which therapies have experienced market growth or decline over the key therapy periods studied? To what extent are key therapies prescribed concomitantly to recently treated patients? What has been the impact of recently approved NP drugs on the treatment of PDN?
Primary patient-level data: This report provides quantitative findings from our analysis of data covering approximately 40 million lives and provides the most representative sample of U.S. treatment practice for Medicare and commercially insured patients. This report is delivered as a key findings slide deck and a dashboard that can be accessed using the Internet and presents claims that are less than six months old at the time of publication.
Patients who are continuously enrolled for the complete two-year study period must meet the following condition: at least one claim with a diagnosis code related to PDN (International Classification of Diseases, Ninth Revision [ICD-9]), which we believe is best encompassed by the diagnostic codes 250.60, 250.61, 250.62, 250.63, 250.9, 250.90, 250.91, 250.92, 250.93, or 357.2, during the study period.
Quantified lines of therapy analysis show exact share of each agent in each line of therapy, including rate of progression between lines and length of time patients are on each line.
Newly Diagnosed Patients:
- Patient share by drug class and key products across three lines of therapy, within one year of diagnosis.
- Patient flowchart through one year of treatment for all first-line products, including progression rates and add/switch behavior.
- Polypharmacy and key concomitant therapies by line of therapy.
- Quarterly trends in patient share by line of therapy.
Recently Treated Patients:
- Quarterly snapshot of patient share by drug class and key products.
- Pathway to key therapy flowcharts tracking the preceding therapy patterns for all key therapies, including add/switch behavior.
- Brand source of business, including share for continuing, new (switches/adds), and new (initial therapy) business.
- Polypharmacy and key concomitant therapies.
- Drug persistence and compliance.
- Quarterly trends in patient share for all key therapies.