Clasteon 400mg capsules

Prescribing Information

Refer to the full Summary of Product Characteristics (SmPC) before prescribing. 

Name and active ingredient: CLASTEON 400mg capsules.

Each capsule contains 400mg sodium clodronate (as the tetrahydrate).

Pharmaceutical form: Hard capsules for oral administration.

The capsules are oblong, white and blue, marked CLASTEON.

Indications: Sodium clodronate is indicated for the management of osteolytic lesions, hypercalcaemia and bone pain associated with skeletal metastases in patients with carcinoma of the breast or multiple myeloma.

Sodium clodronate capsules are also indicated for the maintenance of clinically acceptable serum calcium levels in patients with hypercalcaemia of malignancy initially treated with an intravenous infusion of sodium Clodronate.

Posology: For adults, the recommended dose is 4 capsules (1600mg sodium clodronate) daily.

If necessary, the dosage may be increased but should not exceed a maximum of 8 capsules (3200mg sodium clodronate) daily.

Refer to SmPC section 4.2 for full details and information regarding paediatric and renally impaired patients.

Method of administration: Adequate fluid intake should be maintained during treatment.

The oral bioavailability of bisphosphonates is poor.

Bioequivalence studies have shown appreciable differences in bioavailability between different oral formulations of sodium clodronate, as well as marked inter and intra patient variability.

Dose adjustment may be required if the formulation is changed.

Contraindications: Hypersensitivity to sodium clodronate or to any of the excipients listed in section 6.1 of the SmPC.

Acute, severe inflammatory conditions of the gastrointestinal tract.

Pregnancy and lactation.

Renal failure with creatinine clearance below 10ml/min, except for short term use in the presence of purely functional renal insufficiency caused by elevated serum calcium levels.

Concomitant use of other bisphosphonates.

Special warnings and precautions for use: No information is available on the potential carcinogenicity of clodronate disodium, but patients have been treated in clinical trials for up to 2 years.

The duration of the treatment is therefore at the discretion of the physician, according to the status of the underlying malignancy.

Adequate fluid intake should be maintained during treatment.

Renal impairment: Sodium clodronate should be administered with care to patients with renal impairment (see dose adjustment in SmPC Section 4.2.).

In clinical trials, asymptomatic, reversible elevations of transaminases have occurred, without changes in other liver function tests.

Monitoring of serum transaminases is advised (see SmPC section 4.8).

Dental conditions and osteonecrosis of the jaw: A dental examination with appropriate preventive dentistry should be considered prior to treatment with bisphosphonates in patients with concomitant risk factors (e.g. cancer, chemotherapy, radiotherapy, corticosteroids, poor oral hygiene).

While on treatment, these patients should avoid invasive dental procedures if possible.

For patients who develop osteonecrosis of the jaw while on bisphosphonate therapy, dental surgery may exacerbate the condition.

Osteonecrosis of the external auditory canal: Mainly in association with long-term therapy.

Possible risk factors include steroid use and chemotherapy and/or local risk factors such as infection or trauma.

Irritation of the upper gastrointestinal mucosa: Adverse experiences such as oesophagitis, oesophageal ulcers and oesophageal erosions, in some cases severe and requiring hospitalisation, rarely with bleeding or followed by oesophageal stricture or perforation, have been reported in patients receiving treatment with oral bisphosphonates.

While no increased risk was observed in controlled clinical trials there have been post-marketing reports of gastric and duodenal ulcers with oral bisphosphonate use, some severe and with complications.

Atypical fractures of the femur: Atypical subtrochanteric and diaphyseal femoral fractures have been reported with bisphosphonate therapy, primarily in patients receiving long-term treatment for osteoporosis.

These transverse or short oblique, fractures can occur anywhere along the femur from just below the lesser trochanter to just above the supracondylar flare.

These fractures occur after minimal or no trauma and some patients experience thigh or groin pain, often associated with imaging features of stress fractures, weeks to months before presenting with a completed femoral fracture.

Fractures are often bilateral; therefore the contralateral femur should be examined in bisphosphonate-treated patients who have sustained a femoral shaft fracture.

Poor healing of these fractures has also been reported.

Discontinuation of bisphosphonate therapy in patients suspected to have an atypical femur fracture should be considered pending evaluation of the patient, based on an individual benefit risk assessment.

During bisphosphonate treatment patients should be advised to report any thigh, hip or groin pain and any patient presenting with such symptoms should be evaluated for an incomplete femur fracture.

Excipients: This medicine contains 65.846mg sodium (main component of cooking/table salt) in each 400mg tablet.

This is equivalent to 3.2% of the recommended maximum daily dietary intake of sodium for an adult.

Talk to your doctor or pharmacist if you need 3200mg or more daily for a prolonged period, especially if you have been advised to follow a low salt (sodium) diet.

Interaction with other medicinal products and other forms of interaction: Concomitant use of other bisphosphonates is contraindicated.

As aminoglycosides can cause hypocalcaemia concomitant clodronate should be administered with caution.

Hypomagnesaemia may also occur simultaneously.

Patients receiving NSAID's in addition to sodium clodronate have developed renal dysfunction.

However, a synergistic action has not been established.

Concomitant use of estramustine phosphate with clodronate has been reported to increase the serum concentration of estramustine phosphate by up to 80%.

Clodronate forms poorly soluble complexes with divalent metal ions.

Calcium rich foods, mineral supplements and antacids may impair absorption as sodium clodronate forms complexes with divalent metal ions.

Fertility, pregnancy and breast feeding:

Fertility: In animal studies, clodronate did not cause foetal damage, but large doses decreased male fertility.

No clinical data on the effect of clodronate on fertility in humans are available.

Pregnancy: There are limited amount of data from the use of clodronate in pregnant women.

Sodium clodronate is not recommended during pregnancy and in women of childbearing potential not using effective contraception.

Although in animals clodronate passes through the placental barrier, it is not known if it passes into the foetus in humans.

Furthermore, it is not known if clodronate can cause foetal damage or affect reproduction in humans.

Studies in animals have shown reproductive toxicity (see SmPC section 5.3).

Breast-feeding: It is unknown whether clodronate is excreted in human milk.

A risk to the suckling child cannot be excluded.

Breast-feeding should be discontinued during treatment with sodium clodronate.

Undesirable effects: Common ≥ 1/100 to <1/10: Asymptomatic hypocalcaemia, diarrhoea, nausea, vomiting, levels of transaminases increased - usually within normal range.

Rare ≥ 1/10,000 to <1/1,000: Allergic reaction, symptomatic hypocalcaemia, increased levels of serum parathyroid hormone associated with decreased serum calcium levels, increased levels of serum alkaline phosphatase, levels of transaminases increased to more than twice the normal range without associated abnormal hepatic function, hypersensitivity reaction manifesting as skin reaction e.g. pruritus, urticaria, exfoliative dermatitis, bronchospasm in patients with and without a previous history of asthma, renal function impaired, atypical subtrochanteric and diaphyseal femoral fractures (bisphosphonate class adverse Reaction).

For very rare and frequency unknown, refer to SmPC section 4.8.

Legal classification: POM.

Presentations: Packs of 30 or 120 capsules.

List Price: 30 capsules (£34.96), 120 capsules (£139.83).

Marketing Authorisation Number: PL 51463/0091.

MA Holder: Kent Pharma UK Ltd.

Date of preparation: July 2025.

Ref: UK22/002/02 SmPC December 2024.

Adverse events should be reported. Reporting forms and information can be found at: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store. Adverse events should also be reported to Kent Pharma UK Ltd on 01233 506574 or medical@kentathlone.com  For a copy of the SmPC or further medical information, please contact: medical@kentathlone.com  Additional information available on request.