A Retrospective Study to Assess the Impact of the Use of Interferon in Patients With Chronic Hepatitis C (DECISION)

Sustained virological response (SVR) was defined as virological response at 12 weeks after end of treatment (EOT). Virologic response was either defined as having undetectable (that is, no hepatitis C virus Ribonucleic acid \[HCV RNA\] was detected in the participants' plasma samples) or less than 50 international units/milliliter (IU/mL) HCV RNA (that is, the participants' plasma samples contained traces of HCV RNA at a concentration below the limit of quantification of the viral load assay or no HCV RNA was detected in the samples). EOT= Week 48. Participants who did not have viral load assessment at Week 12 were considered treatment failures, except in the specific case where the lack of assessment was not due to treatment shortening in function of response guided therapy.

Time frame: At Week 60

Population: The intent-to-treat (ITT) population consisted of participants who fulfilled all inclusion/ exclusion criteria. The analysis was performed in participants with virologic response at EOT in each group (16, 126, and 101 respectively).

The average percentage reduction of hemoglobin (Hb) in treatment responders and treatment non-responders between the conventional group, peginterferon alfa-2a plus and peginterferon alfa-2b is presented. Participants with undetectable HCV RNA at specified time points (Weeks 4/12/18/24/48) were considered as treatment responders. Participants with positive viral load (detectable HCV RNA) at end of treatment regardless of the treatment duration were considered as treatment non-responders.

Time frame: Up to Week 72

Population: The ITT population consisted of participants who fulfilled all inclusion/ exclusion criteria. Treatment responders and non-responders for whom data was available were considered for this outcome measure.

An AE is defined as any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. An serious adverse event (SAE) is defined as any untoward medical occurrence that, at any dose, results in death, is life threatening, requires hospitalization or prolongation of existing hospitalization, results in persistent or significant disability/incapacity, is a congenital anomaly/birth defect, or is a significant medical event in the investigator's judgment or requires intervention to prevent one or other of these outcomes.

Time frame: Up to Week 72

Population: The ITT population consisted of participants who fulfilled all inclusion/ exclusion criteria.

The number of participants with Interferon dose reduction rates in function of the interferon type being used are reported

Time frame: At Week 24

Population: The ITT population consisted of participants who fulfilled all inclusion/ exclusion criteria. The analysis was performed in the participants who were available for interferon dose reduction rates in each group (56, 302, and 280 respectively).

The percentage of participants with treatment discontinuation rates due to adverse events (AE) between conventional group, peginterferon alfa-2a and peginterferon alfa-2b is presented.

Time frame: Up to Week 48

Population: The ITT population consisted of participants who fulfilled all inclusion/ exclusion criteria.

The percentage of participants who were treated at interferon application centers and at home and who discontinued treatment is presented. Participants who did not have viral load assessment at Week 12 were considered treatment failures, except in the specific case where the lack of assessment was not due to treatment shortening in function of response guided therapy.

Time frame: Up to Week 48

Population: The ITT population consisted of participants who fulfilled all inclusion/ exclusion criteria. The analysis excluded participants treated at an unknown location (7/62, 10/312, and 23/286 respectively)

An early virologic response (EVR) was defined as a HCV-RNA decrease of at least two logarithmic scales (2 Log) or 100 times the pretreatment value or non-detection at Week 12 of treatment period.

Time frame: At Week 12

Population: The ITT population consisted of participants who fulfilled all inclusion/ exclusion criteria.

Null response or no responders were defined as those participants presenting positive viral load at EOT (regardless of the treatment duration). EOT= Week 48.

Time frame: At Week 48

Population: The ITT population consisted of participants who fulfilled all inclusion/ exclusion criteria.

Rapid virologic response was defined as qualitative or quantitative HCV-RNA (viral load) undetectable (below the lower limit of detection) at Week 4 of treatment period.

Time frame: At Week 4

Population: The ITT population consisted of participants who fulfilled all inclusion/ exclusion criteria.

SVR was defined as virological response at 24 weeks after EOT, EOT= Week 48. Virologic response was either defined as having undetectable (that is, no hepatitis C virus Ribonucleic acid \[HCV RNA\] was detected in the participants' plasma samples) or less than 50 IU/mL HCV RNA (that is, the participants' plasma samples contained traces of HCV RNA at a concentration below the limit of quantification of the viral load assay or no HCV RNA was detected in the samples). Participants who did not have viral load assessment at Week 12 were considered treatment failures, except in the specific case where the lack of assessment was not due to treatment shortening in function of response guided therapy.

Time frame: At Week 72

Population: The ITT population consisted of participants who fulfilled all inclusion/ exclusion criteria. The analysis was performed in participants with virologic response at EOT in each group (16, 126, and 101 respectively).

The percentage of participants with SVR-12 and SVR-24 treated at interferon application centers (IAC) and treated at home are presented.

Time frame: At Week 60 (SVR 12) and Week 72 (SVR 24)

Population: The ITT population consisted of participants who fulfilled all inclusion/ exclusion criteria. The analysis was performed in participants with virologic response at EOT in each group excluding participants treated at an unknown location (2/16, 5/126, and 9/101 respectively).

Virologic relapse was defined as undetectable HCV-RNA at end of treatment and detectable HCV-RNA at the last follow-up assessment available. If the participant was a responder at end of treatment and was not submitted to any viral load assessment during the follow-up period, he was considered a relapser.

Time frame: Up to Week 72

Population: The ITT population consisted of participants who fulfilled all inclusion/ exclusion criteria. The analysis was performed in participants with virologic response at EOT in each group (16, 126, and 101 respectively).

Virologic response at EOT was defined as undetectable HCV-RNA at EOT (regardless in which week treatment was concluded). EOT = Week 48.

Time frame: At Week 48

Population: The ITT population consisted of participants who fulfilled all inclusion/ exclusion criteria.