Ganciclovir Oresund Pharma
Antiviral medicine for cytomegalovirus (CMV) infections – intravenous infusion
Ganciclovir Oresund Pharma is a prescription antiviral medicine containing ganciclovir, used to treat and prevent serious cytomegalovirus (CMV) infections in immunocompromised patients. It is given as a slow intravenous infusion in hospital settings and requires careful monitoring of blood counts and kidney function throughout treatment. This guide covers uses, dosing, side effects, drug interactions, and important safety information based on international clinical guidelines.
Quick Facts
Key Takeaways
- Ganciclovir is a potent antiviral used to treat and prevent CMV infections in immunocompromised patients, especially organ transplant recipients and those with HIV/AIDS.
- It must be administered as a slow intravenous infusion over at least one hour – never as a rapid IV bolus injection.
- Bone marrow suppression (neutropenia, anaemia, thrombocytopenia) is the most significant side effect and requires regular blood count monitoring.
- Dosage must be adjusted in patients with impaired kidney function based on creatinine clearance values.
- Ganciclovir is contraindicated in pregnancy and breastfeeding due to its teratogenic and mutagenic potential in animal studies.
What Is Ganciclovir Oresund Pharma and What Is It Used For?
Ganciclovir is a synthetic nucleoside analogue of 2′-deoxyguanosine that inhibits the replication of human herpesviruses, with particular activity against cytomegalovirus (CMV). Developed as one of the first effective antiviral agents against CMV, ganciclovir has been a cornerstone in the management of CMV disease for decades. The Oresund Pharma formulation is supplied as a sterile lyophilised powder containing 500 mg of ganciclovir per vial, which is reconstituted and diluted before intravenous administration.
Cytomegalovirus is a member of the herpesvirus family that infects a large proportion of the global population. In individuals with healthy immune systems, CMV infection is usually asymptomatic or causes only mild symptoms. However, in people whose immune systems are compromised – whether due to organ transplantation, HIV/AIDS, cancer chemotherapy, or other immunosuppressive therapies – CMV can cause life-threatening disease affecting the eyes (retinitis), lungs (pneumonitis), gastrointestinal tract (colitis, oesophagitis), liver (hepatitis), and central nervous system (encephalitis).
The primary indications for ganciclovir intravenous infusion include:
- Treatment of CMV retinitis in adults with acquired immunodeficiency syndrome (AIDS), which can lead to progressive vision loss and blindness if untreated.
- Treatment of CMV disease (including pneumonitis, colitis, oesophagitis, and hepatitis) in immunocompromised patients.
- Prevention of CMV disease in patients receiving immunosuppressive therapy following solid organ transplantation or bone marrow transplantation who are at risk of CMV reactivation.
- Treatment of congenital CMV infection in neonates with symptomatic central nervous system involvement, under specialist guidance.
Ganciclovir works by being selectively phosphorylated inside CMV-infected cells by a viral kinase (UL97 phosphotransferase), then further phosphorylated by cellular kinases to ganciclovir triphosphate. This active form competitively inhibits the viral DNA polymerase (UL54) and is also incorporated into the growing viral DNA chain, causing premature chain termination. Because the initial phosphorylation step depends on a virus-specific enzyme, ganciclovir achieves much higher concentrations of its active form in infected cells compared with uninfected cells, which contributes to its selective antiviral activity.
According to the European Medicines Agency (EMA) and World Health Organization (WHO), ganciclovir remains an essential antiviral for CMV management, listed on the WHO Model List of Essential Medicines. While oral valganciclovir (the prodrug of ganciclovir with improved oral bioavailability) has replaced intravenous ganciclovir in many clinical settings, the intravenous formulation remains essential for patients who cannot take oral medications, those with severe CMV disease requiring rapid therapeutic drug levels, and in critical care settings.
What Should You Know Before Taking Ganciclovir Oresund Pharma?
Before initiating ganciclovir therapy, a thorough clinical assessment is essential. Your healthcare provider will evaluate your current medical condition, review all medications you are taking, and order baseline laboratory tests including complete blood count with differential, platelet count, serum creatinine, and creatinine clearance. Understanding the potential risks and benefits is crucial for safe and effective use of this medication.
Contraindications
Ganciclovir Oresund Pharma must not be used in the following circumstances:
- Hypersensitivity to ganciclovir, valganciclovir, or any of the excipients in the formulation. Cross-sensitivity between ganciclovir and valganciclovir is expected since valganciclovir is the prodrug of ganciclovir.
- Severe neutropenia (absolute neutrophil count below 500 cells/µL) at baseline, as ganciclovir can further suppress bone marrow function.
- Severe thrombocytopenia (platelet count below 25,000/µL) at baseline, due to the risk of worsening thrombocytopenia and associated bleeding complications.
- Co-administration with didanosine is not recommended due to significantly increased didanosine plasma levels and risk of didanosine toxicity.
Warnings and Precautions
Ganciclovir may cause severe haematological toxicity including neutropenia, anaemia, and thrombocytopenia. Treatment should not be initiated if the absolute neutrophil count is below 500 cells/µL, platelet count is below 25,000/µL, or haemoglobin is below 8 g/dL. Complete blood counts must be monitored regularly throughout treatment.
Several important warnings and precautions apply to ganciclovir therapy:
- Bone marrow suppression: Granulocytopenia (neutropenia), anaemia, and thrombocytopenia have been observed in patients treated with ganciclovir. Complete blood counts and platelet counts should be performed every 2 days during the first 14 days of induction, then at least once weekly. In patients with pre-existing cytopenias or a history of drug-related cytopenias, more frequent monitoring is recommended.
- Renal impairment: Ganciclovir is primarily excreted by the kidneys, and dosage adjustments based on creatinine clearance are mandatory. Adequate hydration should be maintained during treatment. Concurrent use of other nephrotoxic drugs should be avoided where possible.
- Carcinogenicity and mutagenicity: Ganciclovir should be considered a potential carcinogen and mutagen in humans based on animal data. Long-term safety regarding carcinogenic potential in humans has not been fully established.
- Impaired fertility: Animal studies indicate that ganciclovir may cause temporary or permanent inhibition of spermatogenesis and suppression of fertility in females. Patients should be advised of these potential reproductive risks before treatment.
- Infusion site reactions: Ganciclovir solution has a high pH (approximately 11) and must be infused into veins with adequate blood flow. Extravasation can cause severe local tissue irritation and phlebitis. Central venous access is recommended where feasible.
- Seizures: Seizures have been reported in patients receiving ganciclovir, particularly those with underlying CNS pathology, prior seizure history, or concurrent use of imipenem-cilastatin. Use with caution in such patients.
Pregnancy and Breastfeeding
Ganciclovir is contraindicated during pregnancy. Animal reproductive studies have demonstrated that ganciclovir is teratogenic (causes birth defects) in rabbits and embryotoxic in rabbits and mice at doses comparable to the human exposure. There are no adequate and well-controlled studies in pregnant women. If ganciclovir is used during pregnancy, or if the patient becomes pregnant during treatment, she should be informed of the potential hazard to the foetus.
Women of childbearing potential must use effective contraception during ganciclovir treatment and for at least 30 days after the last dose. Men must use barrier contraception during treatment and for at least 90 days after the last dose, as ganciclovir may cause temporary or permanent impairment of spermatogenesis.
Breastfeeding: It is not known whether ganciclovir is excreted in human breast milk. Because many drugs are excreted in breast milk and because of the potential for serious adverse reactions in the nursing infant (including the potential for carcinogenicity and mutagenicity shown in animal studies), breastfeeding must be discontinued during ganciclovir therapy. A decision must be made whether to discontinue breastfeeding or to discontinue the drug, taking into account the importance of the drug to the mother.
How Does Ganciclovir Oresund Pharma Interact with Other Drugs?
Ganciclovir has clinically significant interactions with multiple drug classes. Since ganciclovir is primarily eliminated through the kidneys by both glomerular filtration and active tubular secretion, drugs that inhibit renal tubular secretion or are themselves nephrotoxic may increase ganciclovir plasma levels and toxicity. Additionally, because ganciclovir’s principal dose-limiting toxicity is bone marrow suppression, the concomitant use of other myelosuppressive agents requires careful monitoring.
Major Interactions
| Drug | Effect | Clinical Recommendation |
|---|---|---|
| Imipenem-cilastatin | Generalised seizures reported with concurrent use | Avoid concurrent use unless benefit clearly outweighs risk. Monitor for seizure activity. |
| Zidovudine (AZT) | Additive haematological toxicity; both drugs cause neutropenia and anaemia | If co-administration is necessary, monitor CBC very frequently. Dose reduction of one or both agents may be needed. |
| Didanosine (ddI) | Plasma levels of didanosine increased by 84–111% when given with oral ganciclovir/valganciclovir | Concurrent use is not recommended. If essential, monitor closely for didanosine toxicity (pancreatitis, peripheral neuropathy). |
| Mycophenolate mofetil | Potential for increased plasma levels of both ganciclovir and mycophenolic acid phenolic glucuronide (MPAG) in patients with renal impairment | Monitor for increased toxicity of both drugs. Adjust doses based on renal function and blood counts. |
| Other myelosuppressive agents (e.g. dapsone, pentamidine, flucytosine, vincristine, vinblastine, doxorubicin, trimethoprim/sulfamethoxazole) | Additive bone marrow suppression | Use only if expected benefit outweighs risk. Perform more frequent CBC monitoring. Consider haematopoietic growth factor support. |
Minor Interactions and Other Considerations
| Drug | Effect | Clinical Recommendation |
|---|---|---|
| Probenecid | Reduces renal clearance of ganciclovir by approximately 20%, increasing AUC by approximately 40% | Monitor for increased ganciclovir toxicity. Dose reduction may be needed. |
| Trimethoprim | May compete for renal tubular secretion, potentially increasing ganciclovir levels. Additive myelosuppressive effect. | Monitor renal function and blood counts more frequently. |
| Nephrotoxic drugs (e.g. amphotericin B, ciclosporin, tacrolimus) | Impaired renal function may increase ganciclovir levels and risk of toxicity | Monitor renal function closely. Adjust ganciclovir dose based on creatinine clearance. |
| Tenofovir | Both drugs are renally eliminated; potential for increased exposure to either drug | Monitor renal function. No specific dose adjustment data available; use clinical judgement. |
Patients should inform their healthcare provider of all medications, supplements, and herbal products they are taking before starting ganciclovir therapy. This includes over-the-counter medications and any recently discontinued treatments, as interactions may still be relevant during the washout period.
What Is the Correct Dosage of Ganciclovir Oresund Pharma?
Ganciclovir Oresund Pharma must be administered as a slow intravenous infusion over a minimum of one hour at a concentration not exceeding 10 mg/mL. The reconstituted and diluted solution should be used promptly. Dosing is based on body weight and renal function, and treatment is divided into induction and maintenance phases for most indications.
Adults with Normal Renal Function
| Indication | Induction | Maintenance | Duration |
|---|---|---|---|
| CMV retinitis | 5 mg/kg IV every 12 hours | 5 mg/kg IV once daily (7 days/wk) or 6 mg/kg IV once daily (5 days/wk) | Induction: 14–21 days; Maintenance: until immune reconstitution |
| CMV disease (other organ involvement) | 5 mg/kg IV every 12 hours | 5 mg/kg IV once daily | Induction: 14–21 days; Maintenance: as clinically indicated |
| CMV prophylaxis (transplant) | 5 mg/kg IV every 12 hours for 7–14 days | 5 mg/kg IV once daily (7 days/wk) or 6 mg/kg once daily (5 days/wk) | Continue for 100 days post-transplant or as per institutional protocol |
Renal Impairment Dose Adjustment
Since ganciclovir is primarily excreted by the kidneys, dosage reductions are mandatory for patients with impaired renal function. The following dose adjustments are based on estimated creatinine clearance (CrCl):
| CrCl (mL/min) | Induction Dose | Maintenance Dose |
|---|---|---|
| ≥ 70 | 5 mg/kg every 12 hours | 5 mg/kg once daily |
| 50–69 | 2.5 mg/kg every 12 hours | 2.5 mg/kg once daily |
| 25–49 | 2.5 mg/kg once daily | 1.25 mg/kg once daily |
| 10–24 | 1.25 mg/kg once daily | 0.625 mg/kg once daily |
| < 10 | 1.25 mg/kg 3 times per week (after haemodialysis) | 0.625 mg/kg 3 times per week (after haemodialysis) |
Children and Adolescents
Experience with ganciclovir in paediatric patients is limited. Dosing in children is generally based on body weight and follows the same mg/kg regimen as in adults, with careful attention to renal function. In neonates with symptomatic congenital CMV disease with CNS involvement, the recommended dose is 6 mg/kg IV every 12 hours for 6 weeks, as supported by evidence from the landmark Kimberlin et al. study published in the Journal of Pediatrics. Paediatric use should be under the supervision of a specialist in paediatric infectious diseases.
The safety and efficacy of ganciclovir have not been established in children under 12 years for most indications beyond congenital CMV. Clinical judgement must guide the decision to use ganciclovir in this population, weighing the potential benefits against the risks of haematological toxicity and potential long-term effects on growth and development.
Elderly Patients
No specific dosage adjustment is required based on age alone. However, elderly patients are more likely to have decreased renal function, and dosage should be adjusted according to creatinine clearance as outlined above. Age-related decline in glomerular filtration rate should be considered even when serum creatinine appears normal. Regular monitoring of renal function is particularly important in elderly patients receiving ganciclovir.
Missed Dose
Since ganciclovir is administered in a clinical setting under medical supervision, missed doses are uncommon. If a dose is missed, it should be given as soon as possible. If it is almost time for the next scheduled dose, the missed dose should be skipped and the regular dosing schedule resumed. Do not double the dose to make up for a missed one. Your healthcare team will adjust the treatment schedule as needed.
Overdose
Overdosage with intravenous ganciclovir may result in severe bone marrow suppression, renal toxicity, seizures, liver toxicity, and potentially fatal pancytopenia. There is no specific antidote. In case of suspected overdose, seek immediate medical attention.
Reports of overdosage with intravenous ganciclovir have described the following adverse effects: irreversible pancytopenia, persistent bone marrow suppression, reversible neutropenia and granulocytopenia, hepatitis, renal toxicity, and seizures. Haemodialysis and adequate hydration may be useful in reducing drug plasma levels. The use of haematopoietic growth factors (e.g. G-CSF, GM-CSF) may be considered to manage severe cytopenias resulting from overdose.
What Are the Side Effects of Ganciclovir Oresund Pharma?
Ganciclovir, like all potent antiviral agents, can cause a range of side effects. The most clinically significant adverse effects are haematological (relating to blood cells), which reflect the drug’s mechanism of action on rapidly dividing cells. The frequency and severity of side effects are influenced by the dose, duration of treatment, degree of immunosuppression, concomitant medications, and the patient’s overall health status.
Side effects are classified by frequency according to the MedDRA convention: Very common (≥1/10), Common (≥1/100 to <1/10), Uncommon (≥1/1,000 to <1/100), and Rare (<1/1,000). The following categorisation is based on clinical trial data and post-marketing surveillance.
Very Common (≥1/10)
Affects more than 1 in 10 patients
- Neutropenia (low neutrophil white blood cells)
- Anaemia (low red blood cells)
- Thrombocytopenia (low platelet count)
- Fever / pyrexia
- Diarrhoea
- Nausea and vomiting
- Decreased appetite
- Fatigue
- Elevated serum creatinine
Common (≥1/100 to <1/10)
Affects 1 to 10 in every 100 patients
- Sepsis (serious bloodstream infection)
- Oral candidiasis (oral thrush)
- Urinary tract infections
- Leucopenia (low total white blood cell count)
- Pancytopenia (low levels of all blood cell types)
- Headache
- Insomnia
- Dizziness
- Peripheral neuropathy (nerve damage)
- Abdominal pain
- Constipation
- Elevated liver enzymes (ALT, AST)
- Skin rash and dermatitis
- Night sweats
- Arthralgia (joint pain)
- Cough and dyspnoea (shortness of breath)
- Injection site reactions / phlebitis
Uncommon (≥1/1,000 to <1/100)
Affects 1 to 10 in every 1,000 patients
- Agranulocytosis (severely low granulocytes)
- Seizures / convulsions
- Tremor
- Visual disturbances
- Retinal detachment (in CMV retinitis patients)
- Pancreatitis
- Hepatitis
- Alopecia (hair loss)
- Haematuria (blood in urine)
- Renal failure
- Depression and anxiety
- Confusion and psychosis
Rare (<1/1,000)
Affects fewer than 1 in 1,000 patients
- Aplastic anaemia (bone marrow failure)
- Anaphylactic reactions
- Stevens-Johnson syndrome
- Cardiac arrhythmias
- Male infertility (azoospermia)
- Hearing loss
Contact your healthcare provider immediately if you experience signs of infection (fever, sore throat, chills), unusual bleeding or bruising, significant fatigue or weakness, severe skin rash, visual changes, or seizures. These may indicate serious haematological or neurological adverse effects requiring urgent medical evaluation.
It is important to note that many patients receiving ganciclovir have underlying serious medical conditions and concurrent medications that can also cause similar side effects. Your healthcare team will carefully monitor you throughout treatment to distinguish drug-related adverse effects from symptoms of the underlying disease and to adjust treatment as needed.
How Should You Store Ganciclovir Oresund Pharma?
Proper storage of Ganciclovir Oresund Pharma is essential to maintain the drug’s stability, efficacy, and safety. Since this medication is primarily handled in hospital pharmacies and clinical settings, healthcare professionals should follow institutional protocols alongside the manufacturer’s recommendations.
The following storage guidelines apply:
- Unopened vials: Store below 25°C (77°F). Keep the vials in the original outer carton to protect from light. Do not refrigerate or freeze the dry powder.
- Reconstituted solution: After reconstitution with 10 mL of water for injections, the resulting solution contains 50 mg/mL of ganciclovir. The reconstituted concentrate should be used immediately. If not used immediately, it may be stored at 2–8°C (36–46°F) for up to 24 hours. Do not freeze the reconstituted solution.
- Diluted infusion solution: After further dilution in compatible intravenous fluid (e.g. 0.9% sodium chloride, 5% glucose, or Ringer’s lactate) to a concentration not exceeding 10 mg/mL, the infusion should be administered immediately. If necessary, the diluted solution may be stored at 2–8°C for up to 24 hours from the time of reconstitution. The diluted solution should not be frozen.
- Incompatibilities: Ganciclovir solution is alkaline (pH approximately 11) and should not be mixed with other intravenous medications. It is incompatible with bacteriostatic water for injections containing parabens, as precipitation may occur.
- Disposal: Any unused product or waste material should be disposed of in accordance with local requirements for cytotoxic waste. Ganciclovir is a potential mutagen and carcinogen; appropriate precautions (gloves, protective eyewear) should be used during handling and preparation.
Do not use Ganciclovir Oresund Pharma after the expiry date printed on the vial and carton. If you notice any visible particles, cloudiness, or discolouration in the reconstituted or diluted solution, the preparation should be discarded. Always inspect parenteral drug products visually before administration.
What Does Ganciclovir Oresund Pharma Contain?
Ganciclovir Oresund Pharma is a sterile lyophilised (freeze-dried) powder for concentrate for solution for infusion. Understanding the composition is important for healthcare professionals preparing the infusion and for patients who may have sensitivities to specific excipients.
Active substance: Each vial contains ganciclovir sodium equivalent to 500 mg ganciclovir. Ganciclovir sodium is the sodium salt form of ganciclovir, which provides improved aqueous solubility for parenteral administration. The molecular formula of ganciclovir is C9H13N5O4, and its molecular weight is 255.23 g/mol.
Excipient(s): Sodium hydroxide (for pH adjustment) and hydrochloric acid (for pH adjustment). The pH of the reconstituted solution is approximately 11. The reconstituted solution may also contain residual amounts of the lyophilisation process components.
Appearance: The dry powder is white to off-white. After reconstitution with 10 mL of sterile water for injections, it forms a clear, colourless to slightly yellow solution. Any solution showing particulate matter, precipitates, or unusual discolouration should not be used.
Sodium content: Ganciclovir Oresund Pharma contains sodium. Patients on a controlled sodium diet should take this into account. The exact sodium content per vial should be checked on the product label or package leaflet.
Reconstitution and dilution: The 500 mg vial is reconstituted with 10 mL of water for injections to produce a concentration of 50 mg/mL. The required dose is then withdrawn and further diluted in a compatible IV fluid (typically 100 mL of 0.9% sodium chloride or 5% glucose) to achieve a final concentration not exceeding 10 mg/mL. The infusion is then administered over at least one hour.
Frequently Asked Questions
References
This article is based on the following peer-reviewed sources and international clinical guidelines:
- European Medicines Agency (EMA). Ganciclovir – Summary of Product Characteristics. Available at: www.ema.europa.eu.
- World Health Organization (WHO). WHO Model List of Essential Medicines – 23rd List, 2023. Geneva: WHO; 2023.
- Kotton CN, Kumar D, Caliendo AM, et al. The Third International Consensus Guidelines on the Management of Cytomegalovirus in Solid-Organ Transplantation. Transplantation. 2018;102(6):900-931. doi:10.1097/TP.0000000000002191
- Kimberlin DW, Lin CY, Sanchez PJ, et al. Effect of ganciclovir therapy on hearing in symptomatic congenital cytomegalovirus disease involving the central nervous system: a randomized, controlled trial. J Pediatr. 2003;143(1):16-25.
- British National Formulary (BNF). Ganciclovir. National Institute for Health and Care Excellence (NICE). Available at: bnf.nice.org.uk.
- U.S. Food and Drug Administration (FDA). Cytovene (ganciclovir) Prescribing Information. Available at: www.fda.gov.
- Ljungman P, de la Camara R, Robin C, et al. Guidelines for the management of cytomegalovirus infection in patients with haematological malignancies and after stem cell transplantation from the 2017 European Conference on Infections in Leukaemia (ECIL 7). Lancet Infect Dis. 2019;19(8):e260-e272.
- Rawlinson WD, Boppana SB, Fowler KB, et al. Congenital cytomegalovirus infection in pregnancy and the neonate: consensus recommendations for prevention, diagnosis, and therapy. Lancet Infect Dis. 2017;17(6):e177-e188.
Editorial Team
This article was written and medically reviewed by the iMedic Medical Editorial Team, consisting of licensed physicians with specialist training in infectious diseases, virology, and clinical pharmacology.
iMedic Medical Editorial Team – specialists in infectious diseases, transplant medicine, and clinical pharmacology with documented academic and clinical experience.
iMedic Medical Review Board – independent panel of medical experts who verify accuracy, completeness, and adherence to international clinical guidelines (EMA, FDA, WHO, BNF).
Editorial process: All medical content on iMedic follows a rigorous editorial process including primary research, expert writing, peer review, and regular updates. We adhere to the GRADE evidence framework and ensure all claims are supported by Level 1A evidence where available. Our content is independent and free from commercial funding or pharmaceutical industry influence.