Pamidronate belongs to the drug class known as bisphosphonates whose therapeutic value stems from their ability to inhibit osteoclast-mediated bone resorption.
FDA-approved indications for pamidronate include moderate or severe hypercalcemia of malignancy, moderate to severe Paget disease of bone, osteolytic bone metastases of breast cancer, and osteolytic lesions of multiple myeloma.
Non-FDA-approved indications for pamidronate include: osteoporosis, complex regional pain syndrome, osteoporosis secondary to chronic glucocorticoid use and prolonged immobility, bone loss nonmetastatic hormone-responsive prostate cancer, and osteogenesis imperfecta in children.
The mechanism of action of pamidronate, as well as other bisphosphonates, stems from its chemical structure as a derivative of inorganic pyrophosphate (PPi). Bisphosphonates mimic PPi and bind with high affinity to hydroxyapatite crystals found within areas of remodeling bone. The bound drug is released from its bound hydroxyapatite as osteoclasts begin to resorb bone. The freed drug then leads to apoptosis of osteoclasts via inhibition of the enzyme, farnesyl pyrophosphate synthase. This enzyme is involved in metabolic pathways responsible for the production of cholesterol and other lipids. Despite the ubiquitous nature of this enzyme, bisphosphonate-induced apoptosis via inhibition of farnesyl pyrophosphate only appears in osteoclasts. Pamidronate, and the other newer (nitrogen-containing) bisphosphonates induce osteoclast apoptosis via this mechanism while earlier (non-nitrogen-containing) bisphosphonates do so via disruption of several intracellular ATP-dependent processes.
For the treatment of osteolytic lesions of multiple myeloma and bone metastases of breast cancer, IV pamidronate is administered as 90 mg infusions for at least 2 hours and repeated every 3 to 4 weeks.
For the treatment of hypercalcemia of malignancy, IV pamidronate administration is a single dose of 90 mg for 2 to 24 hours.
For the treatment of Paget disease of bone, IV pamidronate is administered as 30 mg over 4 hours on three consecutive days, or 60 to 90 mg infusion over 2 to 4 hours for two or more nonconsecutive days. For mild disease, a single 90 mg infusion may suffice. For severe disease, several 90 mg infusions may be necessary.
Pamidronate correlates with numerous adverse effects, including hypocalcemia and resulting secondary hyperparathyroidism, acute phase response, musculoskeletal pain, various ocular events, and osteonecrosis of the jaw.
IV Bisphosphonates, like pamidronate, are more likely to cause symptomatic hypocalcemia than oral medications, which usually occurs days after infusion. Prevention of this complication is achievable by making sure patients receive adequate Vitamin D and calcium supplementation approximately two weeks before bisphosphonate infusion.
An adverse effect similar to the acute phase response can occur following the initial pamidronate infusion, which reaches maximal intensity in 28 to 36 hours and self-resolves in 2 to 3 days. It is rarer following subsequent infusions. Patients with this response complain of fever and symptoms of influenza, such as malaise, fatigue, and generalized body pain. In addition to the pain described in cases of an acute phase response, pamidronate can lead to a delayed, painful syndrome characterized as severe and debilitating occurring up to years after the administration of the drug. It can present any time after administration of the drug.
The most common ocular complication following pamidronate use is nonspecific and self-resolving conjunctivitis. More serious ocular complications include scleritis and uveitis, which both warrant immediate discontinuation of the drug.
Osteonecrosis of the jaw (ONJ) is an uncommon but feared side effect of bisphosphonate use. Patients with ONJ may complain of jaw pain, swelling and redness of nearby tissue, loose teeth in the affected region, and the presence of pus. ONJ affects the mandible more often than the maxilla. It is far more common in those receiving IV bisphosphonates. When due to oral drugs, ONJ is milder and responds better to treatment. Incidence of ONJ increases with increasing dose and duration of administration, and the current recommendation is for the careful use of IV bisphosphonate after two years of taking the drug. ONJ is more common in patients receiving bisphosphonate therapy for cancer with bony metastases as opposed to those receiving treatment for osteoporosis.
The IV bisphosphonates pamidronate and zoledronate are also associated with significant nephrotoxicity, which is rare among oral bisphosphonates. The risk of nephrotoxicity increases with larger doses, shorter infusion times, and more frequent dosing intervals. The most common type of nephrotoxicity seen with pamidronate administration is collapsing focal segmental glomerulosclerosis. Renal toxicity due to pamidronate likely increases in patients with malignancy who also have other risk factors for renal impairment such as chronic kidney disease, hypercalcemia, multiple myeloma, hypertension, older age, treatment with chemotherapeutic drugs, and previous bisphosphonate treatment.
Patients treated with pamidronate should have their kidney function closely monitored throughout their treatment with the medication. Clinicians should record serum creatinine before every infusion. In instances of renal deterioration, the patient should not receive the drug until creatinine rises to within 10% of the patient’s baseline level. Electrolyte disturbances can also occur with the drug, and thus magnesium, potassium, phosphorus, calcium, and vitamin D levels should be monitored and corrected if necessary. Patients should also receive monitoring for albuminuria for 3 to 6 months after pamidronate infusion.
Close monitoring of a patient’s creatinine clearance is vital as the administration protocol of pamidronate depends on this value. Infusion time is not affected with creatinine clearance values greater than 60 mL/min, but for values between 30 to 60 mL/min, it is recommended to either decrease the dose of the drug or infuse it over a longer period. Pamidronate infusion is not recommended in patients with creatinine clearance less than 30 mL/min except in cases of fatal calcium levels or those with severe bone disease due to multiple myeloma.
A small number of cases describe symptomatic hypocalcemia following pamidronate administration. In each case, however, patients had pre-existing derangements contributing to their symptoms, including renal insufficiency and low levels of vitamin D secondary to lifestyle, previous GI surgery, and medication history. Recommendations for the management of pamidronate overdose include appropriate correction of the electrolyte disturbance and pre-treatment supplementation with calcium and Vitamin D.
Pamidronate is frequently a therapeutic choice in the management of Paget disease of bone, multiple myeloma, hypercalcemia of malignancy, and bone metastases of breast cancer.) Physicians, nurses, pharmacists, and other members of the interprofessional healthcare team responsible for treating patients receiving this drug must be aware of the value and potential complications associated with this drug. Physicians should take charge of educating the patient about possible side effects of the medication, including osteonecrosis of the jaw, which requires discussion with the patient’s dentist before any procedures. Nephrotoxicity is another feared side effect of pamidronate, and careful monitoring of a patient’s renal function by members of the healthcare team is paramount throughout treatment. Pharmacists should perform complete medication reconciliation for the patient, recognize any potential drug-drug interactions, and report any concerns with the rest of the team. Nurses should be knowledgeable about proper drug administration, be able to detect signs of possible adverse effects and communicate regularly with the physician with any updates. [Level 1] The interprofessional team approach to pamidronate therapy can drive patient outcomes positively while limiting adverse events. [Level 5]
|||Ganesan K,Roane D, Bisphosphonate 2019 Jan; [PubMed PMID: 29262103]|
|||Major P,Lortholary A,Hon J,Abdi E,Mills G,Menssen HD,Yunus F,Bell R,Body J,Quebe-Fehling E,Seaman J, Zoledronic acid is superior to pamidronate in the treatment of hypercalcemia of malignancy: a pooled analysis of two randomized, controlled clinical trials. Journal of clinical oncology : official journal of the American Society of Clinical Oncology. 2001 Jan 15; [PubMed PMID: 11208851]|
|||Reagan P,Pani A,Rosner MH, Approach to diagnosis and treatment of hypercalcemia in a patient with malignancy. American journal of kidney diseases : the official journal of the National Kidney Foundation. 2014 Jan; [PubMed PMID: 24021907]|
|||Kravets I, Paget's Disease of Bone: Diagnosis and Treatment. The American journal of medicine. 2018 Nov; [PubMed PMID: 29752905]|
|||Van Poznak C,Somerfield MR,Barlow WE,Biermann JS,Bosserman LD,Clemons MJ,Dhesy-Thind SK,Dillmon MS,Eisen A,Frank ES,Jagsi R,Jimenez R,Theriault RL,Vandenberg TA,Yee GC,Moy B, Role of Bone-Modifying Agents in Metastatic Breast Cancer: An American Society of Clinical Oncology-Cancer Care Ontario Focused Guideline Update. Journal of clinical oncology : official journal of the American Society of Clinical Oncology. 2017 Dec 10; [PubMed PMID: 29035643]|
|||Mhaskar R,Kumar A,Miladinovic B,Djulbegovic B, Bisphosphonates in multiple myeloma: an updated network meta-analysis. The Cochrane database of systematic reviews. 2017 Dec 18; [PubMed PMID: 29253322]|
|||Zanatta LB,Marcatto C,Ramos CS,Mañas N,Moreira C,Borba V, Use of pamidronate for osteoporosis treatment in public health care in Brazil. Revista brasileira de reumatologia. 2017 Nov - Dec; [PubMed PMID: 29173688]|
|||van Daele PL, Pamidronate in complex regional pain syndrome: effective therapy in CRPS. The Netherlands journal of medicine. 2016 Jan; [PubMed PMID: 26819355]|
|||Drake MT,Clarke BL,Khosla S, Bisphosphonates: mechanism of action and role in clinical practice. Mayo Clinic proceedings. 2008 Sep; [PubMed PMID: 18775204]|
|||Lee OL,Horvath N,Lee C,Joshua D,Ho J,Szer J,Quach H,Spencer A,Harrison S,Mollee P,Roberts AW,Talaulikar D,Brown R,Augustson B,Ling S,Jaksic W,Gibson J,Kalff A,Johnston A,Kalro A,Ward C,Prince HM,Zannettino A, Bisphosphonate guidelines for treatment and prevention of myeloma bone disease. Internal medicine journal. 2017 Aug; [PubMed PMID: 28782211]|
|||Body JJ,Mancini I, Bisphosphonates for cancer patients: why, how, and when? Supportive care in cancer : official journal of the Multinational Association of Supportive Care in Cancer. 2002 Jul; [PubMed PMID: 12136223]|
|||Siris ES,Lyles KW,Singer FR,Meunier PJ, Medical management of Paget's disease of bone: indications for treatment and review of current therapies. Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research. 2006 Dec; [PubMed PMID: 17229018]|
|||Papapetrou PD, Bisphosphonate-associated adverse events. Hormones (Athens, Greece). 2009 Apr-Jun; [PubMed PMID: 19570737]|
|||Gupta M,Gupta N, Bisphosphonate Related Jaw Osteonecrosis 2019 Jan; [PubMed PMID: 30521192]|
|||Perazella MA,Markowitz GS, Bisphosphonate nephrotoxicity. Kidney international. 2008 Dec; [PubMed PMID: 18685574]|
|||Mubarik A,Iqbal AM, Postpartum Cardiomyopathy 2019 Jan; [PubMed PMID: 30521191]|
|||Edwards BJ,Bunta AD,Lane J,Odvina C,Rao DS,Raisch DW,McKoy JM,Omar I,Belknap SM,Garg V,Hahr AJ,Samaras AT,Fisher MJ,West DP,Langman CB,Stern PH, Bisphosphonates and nonhealing femoral fractures: analysis of the FDA Adverse Event Reporting System (FAERS) and international safety efforts: a systematic review from the Research on Adverse Drug Events And Reports (RADAR) project. The Journal of bone and joint surgery. American volume. 2013 Feb 20; [PubMed PMID: 23426763]|
|||Maalouf NM,Heller HJ,Odvina CV,Kim PJ,Sakhaee K, Bisphosphonate-induced hypocalcemia: report of 3 cases and review of literature. Endocrine practice : official journal of the American College of Endocrinology and the American Association of Clinical Endocrinologists. 2006 Jan-Feb; [PubMed PMID: 16524863]|