2013 Re: Length of antiviral treatment
What research was carried out?
The first big trial of oral antiviral treatment reported in 2013. The main purpose of the study was to compare a 6-week course to a 6-month course of the oral drug valganciclovir in babies born with CMV aged less than 30 days. The study was carried out between 2008 and 2013. It was primarily based in the US but 2 out of the 109 study participants came from the UK.
All babies in the study took valganciclovir by mouth for 6 weeks. At the end of the 6 week period, babies were assigned by chance to receive either valganciclovir or placebo (inactive substance) to complete the 6 months of antiviral treatment. Information about hearing loss and developmental milestones was followed up for 2 years.
What did the results say?
The results showed a small positive improvement in the babies who had 6 months of treatment compared with 6 weeks. This improvement was statistically significant when babies were followed up at 12 and 24 months.
There was a slight improvement in levels of hearing loss in those who got 6 weeks of the drug, but a greater improvement was seen in those who got 6 months of treatment.
The infants who got 6 months of treatment also scored higher on parts of the Bayley Scales of Infant and Toddler Development. The differences were statistically significant for language composite and receptive communication.
There was a slight increase in side effects in babies who had six months of treatment.
However this was not at levels of major toxicity. Levels of low white blood cells were also much better than in the previous ganciclovir study.
What is new about this research?
There is now better evidence about the benefits and risks of valganciclovir. Previously, the only published evidence on benefits of CMV treatment was about the intravenous antiviral drug ganciclovir. Over the past few years, some doctors have been prescribing the oral version of the drug, valganciclovir, instead as it is less invasive for babies. This was based on two very small scale studies which suggested that the drug is safe to use and has fewer short term side effects than ganciclovir.
This study compares the benefits and risks of longer vs. shorter valganciclovir treatment. Previous studies have only looked at 6 weeks of treatment.
This study included babies with a wider range and severity of CMV symptoms than previous studies. Previous studies have treated babies with central nervous system symptoms such as brain calcifications and hearing loss. This study included babies who had e.g. low platelet count or petichiae without central nervous system symptoms.
However, this research didn’t directly compare the benefits and risks of valganciclovir treatment with those of ganciclovir treatment or not getting any treatment at all.
What does this mean for families in the UK?
Its exciting to see more research being carried out into treatment options. The results of this study may mean that UK doctors prescribe a longer course of antivirals for babies. However it is important to remember that there are no statutory guidelines for treating and managing CMV in the UK. Recommendations about type and length of treatment will still be made by individual doctors.
The reason that there are no universal guidelines on treatment is that it is a very complex picture. Little is known about the long-term benefits and risks. There are short term side effects which may be a bigger issue for some babies than others. And whilst there are encouraging signs about benefits the effects are small and do not cover all the potential symptoms of CMV.
Further valganciclovir studies are in the pipeline, the picture on antiviral treatment may evolve further over coming years. This study established collaboration between USA and UK and that these centres will be working on more research.
As a result, CMV Action feels that any family who is interested in considering treatment for their baby should have the opportunity to discuss this with an expert who is familiar with the latest research. We therefore recommend that families ask for a referral to their nearest paediatric infectious diseases specialist, or at the very least ensure that their doctor speaks to such a specialist before making recommendations about treatment.
Where can I find out more?
A full description of the research and the results available so far are on the clinical trials website