You will be shown a paragraph from a biomedical research article. Your task is to extract all drug combinations appearing in a specific sentence within in the paragraph. Each drug combination should be assigned to one of the following three categories:

- POS: Indicates a positive interaction between the drugs in the combination; for instance, drugs that have an additive or synergistic effect.
- NEG: Indicates a negative interaction between the drugs in the combination; for instance, combining these drugs might result in adverse side effects, or might reduce their efficacy.
- COMB: Indicates that the drugs are given in combination, but the type of interaction between the drugs cannot be determined based on the provided context.

Please format your answer as a json array. Each entry in the array should itself be an array formatted as [<drug_1>, <drug_2>, ..., <drug_n>, <category>] where <category> is one of the three categories listed above and <drug_1>, ..., <drug_n> are drug names copied verbatim from the input sentence. Different combinations may involve different numbers of drugs; in other words, the `n` in <drug_n> may vary.

As an example, the following output describes two extracted drug combinations; one between two drugs, and one between three drugs:

[["artesunate", "artemether", "COMB"], ["Nifedipine", "Labetalol", "Prazosin", "POS"]]

The paragraph and specific sentence are below. You should only extract relationships expressed in the specific sentence; the paragraph is provided for context.

In your output, return only the json array and no other text. If no drug combinations appear, return an empty array `[]`.

paragraph: Treatment response and overall outcome of patients with relapsed and refractory peripheral T-cell lymphoma compared to diffuse large B-cell lymphoma. The purpose of the study was to assess treatment response and overall outcome in a cohort of patients with relapsed and refractory peripheral T-cell lymphoma and to compare the results with those for patients with diffuse large B-cell lymphoma treated in a similar manner. We retrospectively analyzed data of 40 consecutive adult patients with relapsed and refractory peripheral T-cell lymphoma referred to our institution for consideration of second-line chemotherapy aiming for autologous stem cell transplant between January 1999 and December 2006. A cohort of 126 patients with diffuse large B-cell lymphoma managed similarly served as a comparison group. Most ( ≥ 75 % ) patients received ESHAP ( etoposide , methylprednisolone , cytarabine , cisplatin ) or DHAP ( cisplatin , cytosine arabinoside , dexamethasone ) as salvage chemotherapy . From first relapse/progression, overall survival at 2 years was 54% (95% confidence interval [CI]: 38-76) for the peripheral T-cell lymphoma cohort and 49% (95% CI: 39-60) for the diffuse large B-cell lymphoma cohort (p = 0.098). Overall response rate to salvage chemotherapy was similar between both groups (63% vs. 52%). Post-autologous stem cell transplant, 1-year progression-free survival was 20% (95% CI: 9-48) for patients with peripheral T-cell lymphoma and 47% (95% CI: 36-61) for patients with diffuse large B-cell lymphoma. Two-year overall survival post-autologous stem cell transplant was 43% (95% CI: 26-71) and 54% (95% CI: 43-68), respectively. Patients with relapsed and refractory peripheral T-cell lymphoma and diffuse large B-cell lymphoma showed a similar response to salvage chemotherapy and overall survival. Likely due to imbalances in risk factors at relapse, progression-free survival post-autologous stem cell transplant was inferior in the peripheral T-cell lymphoma group. Strategies aiming to maintain response duration post-autologous stem cell transplant could improve the outcome of patients with peripheral T-cell lymphoma.

sentence: Most ( ≥ 75 % ) patients received ESHAP ( etoposide , methylprednisolone , cytarabine , cisplatin ) or DHAP ( cisplatin , cytosine arabinoside , dexamethasone ) as salvage chemotherapy .
[["etoposide", "methylprednisolone", "cytarabine", "cisplatin", "COMB"], ["cisplatin", "dexamethasone", "COMB"]]