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: The bevacizumab experience in advanced renal cell carcinoma.  Bevacizumab in combination with interferon alfa is now approved for treatment-naïve advanced renal cell carcinoma ( RCC ) in both the US and Europe . Its objective response rates of 30% and progression-free survival rates of 9-10 months are comparable to the other approved first-line multityrosine kinase inhibitors, sunitinib and pazopanib. Its advantages include a different toxicity profile and assurance of administration compliance given its intravenous formulation. Enthusiasm for its use is blunted by the increased costs, the potential infusion-related reactions, the associated interferon-related toxicities, and the inconvenience of its nonoral formulation. Further study is warranted to assess its efficacy both as a single agent and in combination with the targeted agents and other immunotherapies. With multiple agents now available for the treatment of advanced RCC, identification of patient and tumor-specific biomarkers to inform our choice of first-line therapy and the proper sequence of subsequent therapies is imperative.

sentence: Bevacizumab in combination with interferon alfa is now approved for treatment-naïve advanced renal cell carcinoma ( RCC ) in both the US and Europe .
[["Bevacizumab", "interferon alfa", "POS"]]