Table 2.

Impact of different metronomic CPA schedules on the number of rebounding and regressing tumors, the frequency of tumor rebound, and the rate of growth of rebounding tumors. Data shown are based on growth curves presented in Fig. 5. Rebounding tumor growth rates were estimated from Fig. 5B based on the number of days required for regressing tumors to return to the mean initial tumor volume prior to CPA treatment (day 0). Tumors in the CPA/6d and CPA(210)/9d groups were combined for these analyses; both groups were treated with the same CPA dose calculated on a per day basis, and they exhibited similar tumor rebound growth frequency (18-25%; mean value for combined group 21%) and rebound growth rate (45-48 days for rebound to initial tumor volume).

CPA schedule	Rebounding tumors (number)	Regressing tumors (number)	p-value a	Rebound frequency %	Time to rebound to initial tumor volume (number of days)
CPA/12d	12	2	0.00030 b	85.7	21-24
CPA/9d	8	6	0.033	57.6	27-33
CPA/6d-9d	3	7	NS	30	27-33
CPA/6d + CPA(210)/9d	4	15	--	21.1	45-48

^a: p-value obtained by Fisher’s exact test comparing each group to the combined CPA/6d and CPA(210)/9d group. NS, not significant.

^b: p=0.008 and p=0.0011 for separate comparisons to the CPA/6d and CPA(210)/9d treatment groups, respectively.