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: Chemotherapy of advanced non-small cell lung cancer. Patients with advanced NSCLC receive palliative chemotherapy with platinum-based doublets. Cisplatin-based doublets are preferred in patients with good performance status, whereas carboplatin-based protocols are preferred in patients with impaired organ functions (kidney, heart). Customized chemotherapy appears promising but still remains experimental. Improvements of the outcome of first-line chemotherapy have been achieved by the addition of cetuximab in patients with EGFR-positive NSCLC and of bevacizumab in selected patients with non-squamous cell NSCLC. The optimal combination of chemotherapy with targeted therapies remains a challenge. Maintenance therapy and early second-line chemotherapy might improve outcome but are not yet considered as standard treatments. Patients progressing after first-line chemotherapy are treated with docetaxel , pemetrexed or erlotinib . Finally, the efficacy of new anticancer treatments should be assessed by several clinical endpoints with overall survival remaining the most important endpoint in patients with advanced NSCLC.

sentence: Patients progressing after first-line chemotherapy are treated with docetaxel , pemetrexed or erlotinib .
[]