Using a low toxic agent that potentially with anti-inflammatory proprieties, minocycline, we conducted Phase II randomized placebo controlled trial and observed positive effect of reducing fatigue and other symptoms in patients undergoing CRT for NSCLC.Purpose: In patients with non-small cell lung cancer (NSCLC), concurrent chemoradiation therapy (CRT) exacerbates a cluster of difficult-to-manage symptoms, especially cancer-related fatigue. Minocycline is a readily available, low-cost antibiotic with antiinflammatory properties. We conducted a phase 2 randomized, doubleblinded, placebo-controlled trial to investigate the effect of minocycline in reducing CRT-symptom burden in NSCLC. Methods and Materials: Patients with NSCLC scheduled to receive CRT provided consent and were randomized to receive either minocycline (100 mg twice daily) or a matching placebo during 6 to 7 weeks of CRT. Patient-reported fatigue and other symptoms were assessed on MD Anderson Symptom Inventory weekly from the start of CRT for 12 weeks. The primary outcome was 12-week (AE2 days) area under the curve for symptom burden, which was compared between treatment groups. Results: Forty of 49 enrolled patients (80%) were evaluable (19 on minocycline and 21 on placebo). There were no grade 3 þ adverse events related to the study medication. Fatigue was significantly reduced in the minocycline group compared with placebo group during the 12-week trial period (area under the curve Z 31.2 AE 14.2 vs 45.0 AE 20.9, P Z .011), with a large effect size (Cohen's d Z 0.77). Pain (Cohen's d Z 0.54) and shortness of breath (Cohen's d Z 0.55) were also significantly reduced in the minocycline group (all P < .05).