Appendix C. Detail on criteria for audit of the use of interferon alfa (pegylated and non-pegylated) and ribavirin in the treatment of chronic hepatitis C

Appendix C. Detail on criteria for audit of the use of interferon alfa (pegylated and non-pegylated) and ribavirin in the treatment of chronic hepatitis C

Possible objectives for an audit

An audit on the use of pegylated and non-pegylated interferon alfa and ribavirin in the treatment of CHC could be carried out to ensure that combination therapy is used appropriately.

Possible patients to be included in the audit

An audit could be carried out on a reasonable number of people being treated for CHC, for audit purposes. If a large number of people is being treated, a representative sampling strategy is suggested.

Measures that could be used as a basis for audit

The measures that could be used in an audit of pegylated and non-pegylated interferon alfa and ribavirin in the treatment of CHC are as follows.

Criterion

Standard

Exception

Definition of terms

1. An individual with moderate to severe CHC and who is aged 18 years or older is provided with peginterferon alfa and ribavirin combination therapy within licensed indications if he or she meets one of the following:

a. has not been treated previously

with interferon alfa or peginterferon alfa or

b. has been treated previously or is currently being treated with interferon alfa monotherapy or combination therapy or

c. has been previously treated with peginterferon alfa monotherapy only and either responded at the end of treatment but subsequently relapsed, or who was not responding at the end of treatment

100% of individuals who meet one of a–c

A. Peginterferon alfa is contra-indicated; in particular, the patient is pregnant or breastfeeding

B. Ribavirin is contraindicated or is not tolerated, in which case the individual is:

1) treated with peginterferon alfa monotherapy and

2) tested for viral load at 12 weeks of treatment and

3) treated for 48 weeks if the viral load has reduced to less than 1% of its level at the start of treatment or discontinued treatment if the viral load exceeds 1% of its level at the start of treatment

Pegylated interferon alfa includes peginterferon alfa-2a and peginterferon alfa-2b.

'Moderate to severe CHC' means there is histological evidence of significant scarring (fibrosis) and/or significant necrotic inflammation. See criterion 3 for exceptions for carrying out a liver biopsy for this purpose.

Clinicians will need to agree locally on how to measure compliance with licensed indications, for audit purposes and will need to agree on how to define lack of response to treatment (for 1c) for audit purposes.

For exception B, contraindications include: pregnancy, breastfeeding, the presence of severe debilitating medical conditions (particularly of the heart, blood, kidneys or liver), haemoglobinopathies, the presence of autoimmune diseases, severe psychiatric conditions, or haemolytic anaemia.

For the exception, 'not tolerated' can include: influenza-like symptoms (fatigue, headache and fever), decreases in haematological parameters (neutrophil, white blood cell or platelet counts); gastrointestinal complaints such as anorexia or nausea, dermatological symptoms including alopecia, and psychiatric disturbances including depression or anxiety.

2. An individual who meets 1a–c above is treated as follows:

a. for 24 weeks if the individual is

infected with HCV of genotypes and/or 3 or

b. for 12 weeks if the individual is infected with CHC of genotypes 1, 4, 5 or 6 and for 48 weeks if the individual is infected with HCV of genotypes 1, 4, 5 or 6 and the viral load at 12 weeks has reduced to less than 1% of its level at the start of treatment or treatment is discontinued after 12 weeks if the individual is infected with HCV of genotypes 1, 4, 5 or 6 and viral load at 12 weeks exceeds 1% of its level at the start of treatment.

100% of individuals in 1a–c above

None

If an individual is infected with more than one genotype, including at least one of genotypes 1,

4, 5 or 6, treatment should follow 2b and c.

'Reduced to less than 1% of the level at the start of treatment' = at least a 2-log reduction

3. A liver biopsy is carried out on each individual receiving any kind of interferon therapy.

100% of individuals in 1a–c above

A. Liver biopsy poses a significant risk

B. The individual has symptoms of severe extra-hepatic HCV infection sufficient to impair quality of life

For exception A, conditions include haemophilia and individuals who have experienced an adverse event after undergoing a previous liver biopsy.

Clinicians will need to agree locally on how to define severe extra-hepatic HCV infection and quality-of-life impairment, for audit purposes

Calculation of compliance

Compliance (%) with each measure described in the table above is calculated as follows.

Number of patients whose care is consistent with the criterion plus number of patients who meet any exception listed

x 100

Number of patients to whom the measure applies

Clinicians should review the findings of measurement, identify whether practice can be improved, agree on a plan to achieve any desired improvement and repeat the measurement of actual practice to confirm that the desired improvement is being achieved.