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: Comparing the individual effects of metformin and rosiglitazone and their combination in obese women with polycystic ovary syndrome: a randomized controlled trial. To compare the effects of metformin, rosiglitazone, and their combination in obese polycystic ovary syndrome (PCOS) patients with insulin resistance. ### design Prospective randomized controlled trail. ### setting Tertiary teaching hospital. ### Patient S Obese Chinese women (body mass index [BMI] ≥25 kg/m ### Intervention S In group 1, 68 patients administered metformin (1,500 mg/day); in group 2, 67 patients administered rosiglitazone ( 4 mg/day ) ; in group 3 , 69 patients administered metformin ( 1,000 mg/day ) and rosiglitazone ( 4 mg/day ) for 6 months , all with the same diet and regular exercise lifestyle recommendation. ### Main Outcome Measure S Average menstrual interval, anthropometric measurements, androgen-related parameters, and metabolic features of insulin, carbohydrates, and lipids, with intention-to-treat analysis. ### Result S The baseline parameters showed no statistically significant differences. After the 6-month treatment, most participants showed an improved menstrual pattern. There were statistically significant decreases in acne scores, weight, BMI, waist circumference, waist-to-hip ratio, and serum testosterone. The metabolic indexes of insulin, carbohydrates, and lipids were improved obviously compared with the baseline in each group. Among the three groups, the patients administered 1,500 mg/day metformin experienced greater reductions in weight. However, the rosiglitazone users (alone or combined with metformin) showed a more notable decline in total cholesterol and triglyceride levels. ### Conclusion S Considering the benefits of metformin on weight loss, high-dose metformin (1,500 mg/day) along with lifestyle modification should be recommended for obese, insulin-resistant women with PCOS. rosiglitazone alone or combined with low-dosage metformin plus lifestyle modification should be considered for the women with abnormal lipid profiles. ### Clinical Trial Registration Number ChiCTR-TRC-13003642 (Chinese Clinical Trial Registry).

sentence: ( 4 mg/day ) ; in group 3 , 69 patients administered metformin ( 1,000 mg/day ) and rosiglitazone ( 4 mg/day ) for 6 months ,
[["metformin", "rosiglitazone", "POS"]]