Hepatitis C (HCV) is major global problem however it isn’t homogenous as there is much country to country variation in terms of prevalence and genotype distribution. Factors which contribute to this lack of homogeneity include insufficient prevention and detection, limited access to diagnostics and treatment and differences in modes of infection e.g. Intravenous drug use in Europe and North America while there is increased iatrogenic exposure in Middle East and Africa.
To meet the challenge of the HCV epidemic and for its ultimate eradication, there is a need to have a globally co-ordinated strategy which includes effective prevention measures (e.g. Needle exchange and safe blood supplies), good screening/diagnostic programmes and the widespread use of todays’ effective treatments.
Currently HCV is an epidemic that is not being treated due to a lack of awareness of the infection and low treatment rates. This along with need for earlier diagnosis and larger screening programmes means that the landscape for Hepatitis C therapy is rapidly evolving.
As mentioned earlier, HCV is not a single virus but it exists in a number of forms and genotypes, so knowing the patient genotype is important as it helps identify which drug regimen is appropriate, how long treatment should continue and the likelihood of success.
Current HCV treatments can generally be divided into 4 options.
- PEG-IFN and Ribavirin: This regimen benefits in that it is widely available, relatively inexpensive and applicable to all genotypes but it does suffer from a high incidence of adverse events, requires a long treatment duration and it has low sustained viral response(SVR) rates especially in genotype 1 patients
- IFN-Sparing drugs: These regimens are generally a combination PEG-IFN (+/- Ribavirin) with a DAA which give significantly improved SVR rates but are more expensive and are not suitable for all genotypes.
- IFN-free drugs: These are usually a combination of 2 or more DAAs, eliminate the need for injections, have reduced side effects when compared to IFN and have excellent SVR rates. However, they are significantly more expensive than options 1 & 2 and are not yet available in all countries.
- “Wait and see”: With this option doctors and patients wait and hope that better treatments will appear sometime but this is a risky approach as the disease my progress and tomorrow may never come!
At the end of 2014, AbbVie received FDA approval of their new Viekira Pak “3D” treatment for HCV. This is known as “3D”as it is composed of three different classes of direct-acting antivirals – Ombitasvir, Paritaprevir and Daabuvir. In many studies this has been shown to be very effective in the treatment of genotype 1 with a cure rate between 95-100% including patients who have previously failed on other HCV drugs.
A number of challenges remain as to what is the most appropriate treatment for HCV which include (i) Identification of the optimal treatment regimen (ii) Ensuring adequate access for all patients and (iii) improvements to SVR rates in both cirrhotic and non-cirrhotic patient groups.
The EASL treatment indications from 2015 recommended the following:
- All treatment-naïve and experienced patients with compensated disease due to HCV should be considered for therapy
- Treatment should be prioritized for patients with significant fibrosis (Metavir score F3-F4)
- Treatment is justified in patients with moderate fibrosis (Metavir score F2)
- In patients with no or mild disease (METAVIR score F0-F1), the indication for and the timing of therapy should be individualized.
- Patients with decompensated cirrhosis and who are on the transplant list should be considered for IFN-free, ideally Ribavirin-free therapy
Questions about the availability of therapy for all patients, as to whether there should be an age limitation and the need to treat special population are still open. This said, the future looks bright for HCV sufferers as more individualized, shorter duration therapy with pan-genotypic activity will become available.
*HCV treatment landscape is a very fast moving field. To get latest and up to date list of drugs approved and available in the market please visit this link: Hepatitis C New Drug Research