Denosumab

INTRODUCTION

Indications

Treatment of osteoporosis postmenopausal women who are at high risk for fracture or those who have failed/are intolerant of conventional osteoporosis therapy.

Action

A monoclonal antibody that binds specifically to the human receptor activator of nuclear factor kappa-B-ligand (RANKL), which is required for formation, function, and survival of osteoclasts. Binding inhibits osteoclast formation, function, and survival; Therapeutic Effects: ↓ bone resorption with ↓ occurrence of fractures (vertebral, nonvertebral, hip).

Adverse Reactions/Side Effects

GI: PANCREATITIS. GU: cystitis. Derm: dermatitis, eczema, rashes. F and E: hypocalcemia. Metab: hypercholesterolemia. MS: back pain, extremity pain, musculoskeletal pain, osteonecrosis of the jaw, suppression of bone turnover. Misc: infection.

PHYSICAL THERAPY IMPLICATIONS

Examination and Evaluation

• Watch for signs of pancreatitis, including upper abdominal pain (especially after eating), indigestion, weight loss, and oily stools. Report these signs to the physician immediately.

• Assess any pain in the back or extremities. Report persistent or increased musculoskeletal pain to determine presence of bone or joint pathology, including fracture. Be especially aware of possible mouth and jaw pain due to osteonecrosis of the jaw.

• Watch for signs of low calcium levels (hypocalcemia), including tingling sensations in the fingers toes and around the mouth, and for signs of muscle hyperexcitability (cramping, twitching, spasms, tetany). Notify physician immediately if these signs occur.

• Be alert for signs of infection, including fever, sore throat, chills, nausea, vomiting, diarrhea, and localized inflammation. Report these signs to the physician immediately.

Interventions

• Institute weight-bearing and resistance exercises as tolerated to maintain or increase bone mineral density. Start with low-impact or aquatic programs in patients with extensive demineralization, and increase exercise intensity slowly to prevent fractures.

• Protect against falls and fractures (See Appendix E). Modify home environment (remove throw rugs, improve lighting, etc.) and provide assistive devices (cane, walker) or other protective devices as needed to improve balance and prevent falls.

Patient/Client-Related Instruction

• Advise patient about the benefits of proper diet in sustaining bone mineralization. If necessary, refer patient for nutritional counseling about supplemental calcium and vitamin D.

• Encourage patient to modify behaviors that increase the risk of osteoporosis (stop smoking, reduce alcohol consumption).

• Advise patient that this drug may cause problems in fat metabolism (hypercholesterolemia). Remind patient that periodic blood tests may be needed to monitor plasma lipids.

• Instruct patient to report other troublesome side effects such as severe or prolonged bladder pain or skin reactions (rash, dermatitis, eczema).

Pharmacokinetics

Absorption: Well absorbed following subcutaneous administration.

Distribution: Unknown.

Metabolism and Excretion:...