Patients in this prospective multicenter phase II study will be randomized between two first-line therapy strategies for advanced stages of cHL. In the Nivo-AVD cohort, patients will receive 2 cycles of nivolumab monotherapy followed by a switch to Nivo-AVD combination therapy (total of 6 cycles); in the Standard cohort, patients will receive therapy according to current clinical guidelines in Russian Federation for first-line therapy of cHL, which include starting first-line therapy with 2 cycles of BEACOPP-like regimens and, after assessing response after 2 courses, switching to A(B)VD or continuing with BEACOPP-like regimens

Inclusion Criteria:

• Patients with newly diagnosed histologically confirmed stage IIB, III or IV classical hodgkin lymphoma who have not previously received specific therapy;
• Patients with evidence of lesion extent assessed by whole-body PET/CT;
• Patients aged 18-60 years;
• ECOG 0-2;
• Use of highly effective contraceptive methods from the moment of signing the informed consent form, throughout the study and within 6 months after receiving the last dose of the drug;

Exclusion Criteria:

• Severe organ failure: creatinine > 2 norms; alanine aminotransferase, aspartate aminotransferase > 5 norms; bilirubin> 1.5 norms;
• Respiratory failure > grade 1 at the time of enrollment
• Requirement for vasopressor support at the time of enrollment
• Uncontrolled bacterial or fungal infection at the time of enrollment
• Active or prior documented autoimmune disease requiring systemic treatment
• Pregnancy, breastfeeding, planning pregnancy or parenthood during the study period
• Hypersensitivity or allergy to study drugs
• Somatic or mental pathology that does not allow to perform research procedures, including the signing of informed consent
• Simultaneous use of drugs or medical devices studied in other clinical trials