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: Palbociclib in combination with fulvestrant in patients with hormone receptor-positive, human epidermal growth factor receptor 2-negative advanced breast cancer: PALOMA-3 subgroup analysis of Japanese patients. In the double-blind, phase 3 PALOMA-3 study, palbociclib-fulvestrant significantly prolonged progression-free survival versus placebo-fulvestrant in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) metastatic breast cancer (MBC) whose disease had progressed on prior endocrine therapy. The present study evaluated the efficacy, safety, and pharmacokinetics of palbociclib plus fulvestrant in Japanese patients enrolled in PALOMA-3. ### methods Pre/peri/postmenopausal women with HR+/HER2- MBC were randomized 2:1 to fulvestrant ( 500 mg ) and either palbociclib ( 125 mg/day ; 3 weeks on/1 week off ; n = 347 ) or placebo ( n = 174 ) . Prespecified exploratory analyses compared the efficacy ( data cutoff : October 23 , 2015 ) , safety , and pharmacokinetics ( data cutoff : December 5 , 2014 ) in Japanese women versus the overall population . ### results A total of 35 Japanese women were randomized to palbociclib-fulvestrant (n = 27) or placebo-fulvestrant (n = 8). Median progression-free survival was 13.6 months (95% CI, 7.5-not estimable) in the Japanese palbociclib-fulvestrant group and 11.2 months (95% CI, 5.6-not estimable) in the placebo-fulvestrant group. The most common adverse event (AE) in Japanese patients was neutropenia (all grades, 93%); no discontinuations were due to an AE. Geometric mean trough concentration values (within-subject mean steady state) for palbociclib were similar for Japanese Asian (excluding Japanese), and non-Asian patients (84.4 ng/mL, 86.3 ng/mL, and 74.8 ng/mL, respectively). ### Conclusion S The results for the overall population and Japanese patients in PALOMA-3 suggest that palbociclib plus fulvestrant was effective and well tolerated in Japanese patients with HR+/HER2‒ MBC whose disease had progressed on prior endocrine therapy (Pfizer; NCT01942135).

sentence: Pre/peri/postmenopausal women with HR+/HER2- MBC were randomized 2:1 to fulvestrant ( 500 mg ) and either palbociclib ( 125 mg/day ; 3 weeks on/1 week off ; n = 347 ) or placebo ( n = 174 ) . Prespecified exploratory analyses compared the efficacy ( data cutoff : October 23 , 2015 ) , safety , and pharmacokinetics ( data cutoff : December 5 , 2014 ) in Japanese women versus the overall population .
[["fulvestrant", "palbociclib", "POS"]]