Specialty Pharmaceuticals: Therapy Class Review: Osteoarthritis

Mr. Allinson is chief executive officer and chief clinical officer of Therigy, LLC.

Two different types of osteoarthritis (OA) exist—primary and secondary. Primary OA is associated with aging and is thought of as “wear and tear” OA. It is a degenerative joint disease and is the most common type of arthritis affecting mostly middle-aged and older people. It most commonly occurs in the weight-bearing joints of the hips, knees, and spine. It also can affect the fingers, thumb, neck, and large toe. It usually does not affect other joints unless previous injury or excessive stress is involved. OA arises from problems with the cartilage that cushions the ends of bones. The cartilage serves as the body’s “shock absorber,” reducing friction in the joints as the body moves. As the cartilage deteriorates, tendons and ligaments stretch, causing pain. If the condition worsens, the bones could rub against each other. Secondary OA is associated with a direct cause of the disease such as injury, obesity, work history, participation in certain sports, history of joint trauma, genetic predisposition, among others.^1-3

Demographic/Prevalence Data

• 46 million adults have physician-diagnosed arthritis (about 1 in 5 adults).

• Nearly 27 million adults have clinical OA.

• The risk of arthritis increases with age and is more common among women than men.⁴

• The number of adults with physician-diagnosed arthritis is projected to increase to 67 million by 2030. • Before age 45, more men than women have OA; after age 45 it is more common in women.

Current Market Observations

Although various manufacturers are completing trials to expand the use of the hyaluronate products, the products are already being used off-label with clinical success. This market will continue to see growth as the current products (Table) gain indications for small joints such as the shoulder, thumb, and elbow. Synvisc-One has already met with great success in Europe and has been cleared by the FDA to be used in the United States. As a domino effect, its approval will pave the way for other manufacturers to develop a one-time injection as well. Because the products essentially work the same way with equivalent efficacy, the increased competition should become a win-win situation for the patients who use them.^5,6 â– 

References

1.

CDC Arthritis overview, 1-11-08. http://www.cdc.gov/arthritis/arthritis/osteoarthritis.htm#2. Accessed 7-30-09.

2.

WebMD Internet Website. www.WebMD.com/ Accessed 11-1-09.

3.

Arthritis Foundation Website. www.arthritis.org/ Accessed 11-1-09.

4.

National Institute of Arthritis and Musculoskeletal and Skin Diseases. www.niams.nihy.gov/ Accessed 11-1-09.

5.

Lexi-Comp Online

, Hudson, Ohio: Lexi-Comp, Inc.; 2007; January 29, 2007.

6.

Buys Lucinda M, Elliott Mary E, "Chapter 95. Osteoarthritis" (Chapter). Joseph T. DiPiro, Robert L. Talbert, Gary C. Yee, Gary R. Matzke, Barbara G. Wells, L. Michael Posey: Pharmacotherapy: A Pathophysiologic Approach, 7e: http://www.accesspharmacy.com.lp.hscl.ufl.edu/content.aspx?aID=3211428.

7.

Biopharm Insight database. Accessed

7-30-09

.

8.

US Food and Drug Administration website. www.FDA.gov. Accessed

7-30-09

. Accessed 11-1-09.

9.

Center Watch Clinical Trials Listing Service. www.centerwatch.com. Accessed

7-30-09

.

10.

US Clinical Trials Website. www.clinicaltrials.gov. Accessed

7-30-09

. Accessed 11-1-09.

11. Pharmaceutical News and Articles. www.drugs.com. Accessed 7-30-09. Accessed 11-1-09.

12. Wyeth Clinical Trial Listings. http://www.wyeth.com/ClinicalTrialListings?query=Osteoarthritis. Accessed 7-30-09. Accessed 11-1-09.

13. Pfizer Pipeline. http://media.pfizer.com/research/pipeline/pipeline.jsp. Accessed 7-30-09.

14. Nicox Update. www.nicox.com/ Accessed 11-1-09.