A randomized double-blind placebo controlled clinical study was undertaken to investigate the safety and efficacy of a plant-based formulation (DCBT1234-Lung KR), which earlier through 2 trials was found to improve FEV₁ and the quality of life of COPD patients.

The efficacy of DCBT1234-Lung KR was assessed using pulmonary function tests, arterial blood gas (ABG) analyses and the clinical symptoms of COPD in a 6-month study period against a matching placebo and a biomedical drug combination (salbutamol+theophylline+bromhexine).

One hundred and five subjects aged between 35 and 85 years with a smoking history of more than 20 pack years, showing little or no improvement in FEV₁ upon a bronchial challenge of 200μg of inhaled salbutamol and exhibiting ABG percentage of less than 85% of oxygen saturation were taken up for the study. The study had 3 arms viz., the plant-based formulation (DCBT1234-Lung KR), placebo and salbutamol (12mg/day) plus theophylline (300mg/day) plus bromhexine (24mg/day). The end point of the study was determined as an improvement of FEV₁ by 200mL and/or increased ABG values (>90% PaO₂) and clinical symptoms like dyspnoea, wheezing, cough, expectoration, disability, and sleep disturbances.

DCBT1234-Lung KR patients showed statistically significant (95% level) improvement in FEV₁ and PaO₂ in comparison with salbutamol+theophylline+bromhexine and placebo patients. Twenty-three per cent of DCBT1234-Lung KR patients, 19% of salbutamol+theophylline+bromhexine group and 12% of placebo group patients showed the desired 200mL improvement in FEV₁ values in comparison with the other 2 arms. Improved PaO₂ was observed in 15.4% of the DCBT1234-Lung KR patients while no improvement was seen with patients in any other arms. Symptoms like dyspnoea, wheezing, cough, expectoration, disability and sleep disturbances also significantly reduced in DCBT1234-Lung KR and the biomedical group patients, but not in the placebo arm.

DCBT1234-Lung KR was equivalent, if not better than the present day treatment with salbutamol, theophylline and bromhexine combination in COPD patients and this was ascertained using FEV₁ and ABG values.