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: Comparison of CBV, BEAM and BEAC high-dose chemotherapy followed by autologous hematopoietic stem cell transplantation in non-Hodgkin lymphoma: Efficacy and toxicity. Limited data are available to guide the choice of conditioning regimen before autologous hematopoietic stem cell transplantation (AHSCT) for patients with lymphoma. ### methods We analyzed 129 non-Hodgkin lymphoma patients who underwent AHSCT from 1996 to 2013 using the most common regimens : CBV ( cyclophosphamide , carmustine and etoposide ; n = 16 ) , BEAM ( carmustine , etoposide , cytarabine and melphalan ; n = 36 ) and BEAC ( carmustine , etoposide , cytarabine and cyclophosphamide ; n = 77 ) . ### results At a median follow-up of 42.5 months, the estimated 5-year overall survival for the CBV, BEAM and BEAC groups was 68.8%, 77.8% and 81.8%, respectively (P = 0.584). The estimated 5-year progression-free survival in the CBV group (43.8%) was relatively inferior to the BEAM (66.7%) and BEAC (67.5%) groups, but the differences were not significant (P = 0.403). Grade 2 or higher mucositis, diarrhea and fever were relatively more common in the BEAM group (P < 0.05). No differences were observed in the time to hematopoietic recovery and the duration of hospitalization. The amount of transfused platelet was significantly less in the CBV. ### conclusion CBV, BEAM and BEAC regimens are all optional high-dose chemotherapy before AHSCT for NHL patients.

sentence: We analyzed 129 non-Hodgkin lymphoma patients who underwent AHSCT from 1996 to 2013 using the most common regimens : CBV ( cyclophosphamide , carmustine and etoposide ; n = 16 ) , BEAM ( carmustine , etoposide , cytarabine and melphalan ; n = 36 ) and BEAC ( carmustine , etoposide , cytarabine and cyclophosphamide ; n = 77 ) .
[["cyclophosphamide", "carmustine", "etoposide", "POS"], ["carmustine", "etoposide", "cytarabine", "melphalan", "POS"], ["etoposide", "cytarabine", "cyclophosphamide", "carmustine", "POS"]]