OBJECTIVETo objectively evaluate the clinical efficacy of Gulling Pa'an Capsule (GPC), a Chinese medicine, in treating Parkinson's disease (PD).

METHODSAccording to the good clinical practice (GCP) principle, a multi-centered, double-blinded, layered, randomized and grouping-controlled clinical trial was carried out from May 2002 to January 2005 on 242 PD patients. Among them, 53 patients who had never received levodopa were randomized into two groups, 28 in group A treated with GPC, and 25 in group B treated with placebo; patients who had received levodopa were assigned depending on the Hoehn & Yahr (H-Y) grade, to 4 groups, 75 and 19 of grade 1.5 -3 in group C and E, respectively, 79 and 16 of grade 4 in group D and F, respectively, patients in group C and E were treated with GPC and Levodopa, and those in group D and F treated with placebo and Levodopa for control. The treatment course was 12 weeks for all. Changes of unified Parkinson's disease rating scale (UPDRS) II/III scores in comparing with the baseline were assessed. For the groups C, D, E and F, the dosage of levodopa administered was also recorded. Meanwhile, the blood pressure, pulse rate, blood and urine routine, liver and renal functions, electrocardiogram (ECG) and adverse reactions were monitored as the indices for safety supervise.

RESULTS(1) After treatment, symptoms were markedly improved in 1 out of the 28 patients in group A and improved in 11, the markedly improving rate was 3.6% and the improving rate 39.3%; while in group B, the corresponding outcomes were 0 (0/25) and 28.0% (7/25) respectively, showing insignificant difference between the two groups. UPDRS scores, including the total, II and III scores were all significantly lowered in group A after treatment (P < 0.01, P < 0.05); while in group B, significant lowering only showed in terms of UPDRS III (P < 0.05); but the inter-group comparison of the changes in all the three items showed no significant difference. (2) The significant improving rate was 12.0% (9/75) and improving rate 48.0% (36/75) in group C, while those in group D, 12.7% (10/79) and 24.1% (19/79) respectively, the efficacy in group C was better (P < 0.05). The items of 3 UPDRS scores in groups C and D were all significantly lowered after treatment (P < 0.01), and the lowering in group C was more significant in terms of the total and II scores (P < 0.05). (3) The significant improving rate was 5.3% (1/19) and improving rate 36.8% (7/19) in group E, while in group F 0% (0/19) and 25.0% (4/16), respectively, showing insignificant difference between them; UPDRS scores lowered significantly in the two groups after treatment (P < 0.01), also showed no statistical significance in comparison (P > 0.05). (4) The dosage of Levodopa required in groups C and E was significantly reduced after treatment (P < 0.05), while in groups D and F, it was unchanged (P > 0.05); yet, the further analysis displayed that significant reduction only presented in group C (P < 0.05), not in the other three groups.

CONCLUSIONSThe overall efficacy of levodopa in combined with GPC for treating PD patients of H-Y grade 1.5 -3 is significantly higher than that of levodopa alone. GPC shows obvious effects in improving patients' motor syndrome and the quality of life; as used in combining with levodopa, the dosage of levodopa required could be reduced.