Inclusion Criteria:

- Patients with relapsed PTCL according to WHO criteria who have received max. two
previous treatments for PTCL

- Age ≥ 18 years.

- Adequate bone marrow function i.e. absolute neutrophile count of > 1000/µl and
thrombocytes > 75,000/µl.

- Alkaline phosphatase and transaminases ≤ 2,5 x upper limit of normal (ULN)

- Total bilirubin ≤ 2,5 x ULN

- Creatinine clearance ≥ 50 ml/min

- Female subjects of childbearing potential† must: Understand that the study medication
could have an expected teratogenic risk and agree to use, and be able to comply with,
effective contraception and agree to have a medically supervised pregnancy test

- Male subjects must agree to use condoms and agree not to donate semen

Exclusion Criteria:

- Prior history of malignancies, other than PTCL, unless the subject has been free of
the disease for ≥ 3 years

- Prior allogeneic bone marrow transplant or plans to undergo autologous/ allogeneic
bone marrow transplant within 4 weeks of the initiation of vorinostat administration

- Prior treatment with a HDAC inhibitor

- Prior treatment with Lenalidomide (patients previously treated with Thalidomide may
be enrolled)

- Known history of Deep Vein Thrombosis (DVT) and/ or pulmonary embolism (PE)