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: Phase II Study of S-1 and Paclitaxel Combination Therapy in Patients with Previously Treated Non-Small Cell Lung Cancer. In terms of efficacy and safety, good results were obtained with S-1 and paclitaxel (PTX) combination therapy.The findings suggest that S-1 and PTX combination therapy is a feasible treatment option in patients with previously treated non-small cell lung cancer. ### background Although monotherapy with cytotoxic agents , including docetaxel and pemetrexed , is recommended for patients with previously treated advanced non-small cell lung cancer ( NSCLC ) , its outcomes are unsatisfactory . S-1 is an oral fluoropyrimidine agent that consists of tegafur, 5- chloro-2, 4-dihydroxypyridine, and potassium oxonate. S-1 is approved for patients with gastric cancer in 7 Asian countries and 15 European countries. It is also approved for patients with eight type of cancers, including NSCLC, in Japan. We evaluated the efficacy and toxicity of S-1 and paclitaxel (PTX) combination therapy in patients with previously treated NSCLC. ### methods Oral S-1 was administered thrice weekly on days 1-14 at 80, 100, and 120 mg/day in patients with body surface areas of <1.25, 1.25-1.5, and >1.5 m ### results Forty patients were enrolled, with response and disease control rates of 27.5% and 75.0%, respectively (Fig. 1). Median PFS and OS were 6.5 and 20.7 months, respectively. Grade 3/4 anemia and thrombocytopenia were seen in five (12%) and one (2%) patients, respectively. Febrile neutropenia occurred in three patients (7%). Common grade 3/4 nonhematological toxicities were stomatitis (5% of patients), diarrhea (7% of patients), and interstitial lung disease (one patient). No treatment-related deaths were observed. ### conclusion This S-1 and PTX cotherapy dose and schedule showed satisfactory efficacy, with mild toxicities, in patients with previously treated advanced NSCLC.

sentence: Although monotherapy with cytotoxic agents , including docetaxel and pemetrexed , is recommended for patients with previously treated advanced non-small cell lung cancer ( NSCLC ) , its outcomes are unsatisfactory .
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