Estimation of relative biological effectiveness of 225Ac compared to 177Lu during [225Ac]Ac-PSMA and [177Lu]Lu-PSMA radiopharmaceutical therapy using TOPAS/TOPAS-nBio/MEDRAS

EJNMMI Physics

Table 4 Estimated fit parameters for ²²⁵Ac

Cell geom.	Intern.		\(b_{{{\text{init}}}} , {\text{DSB}}s \, {\text{Gy}}^{ - 1}\)	\(b_{{{\text{repair}}}} , {\text{DSB}}s\, {\text{ Gy}}^{ - 1}\)
1	int.	2D	163.10 ± 1.82	145.36 ± 1.90
1	membr.	2D	160.81 ± 1.94	144.95 ± 1.98
2	int.	2D	161.95 ± 1.81	143.88 ± 1.96
2	membr.	2D	161.97 ± 1.91	144.90 ± 2.04
3	int.	2D	157.35 ± 1.74	137.71 ± 1.75
3	membr.	2D	159.63 ± 2.35	142.29 ± 2.68
4	int.	2D	157.15 ± 2.44	137.76 ± 2.59
4	membr.	2D	163.13 ± 2.37	143.89 ± 2.47
5	int.	2D	160.69 ± 2.36	141.67 ± 2.51
5	membr.	2D	160.12 ± 2.73	142.74 ± 2.84
1	int.	3D	166.60 ± 1.16	152.99 ± 1.23
1	membr.	3D	166.96 ± 1.13	154.34 ± 1.20
2	int.	3D	164.56 ± 1.36	150.75 ± 1.46
2	membr.	3D	167.69 ± 1.17	154.83 ± 1.25
3	int.	3D	169.71 ± 1.32	156.25 ± 1.39
3	membr.	3D	165.86 ± 1.30	152.59 ± 1.36
4	int.	3D	164.95 ± 1.14	150.78 ± 1.21
4	membr.	3D	164.47 ± 1.17	149.65 ± 1.20
5	int.	3D	164.49 ± 1.32	150.94 ± 1.40
5	membr.	3D	165.55 ± 1.34	152.14 ± 1.40

\(b_{{{\text{init}}}}\) and \(b_{{{\text{repair}}}}\) denote \(b_{{{}_{{}}^{225} {\text{Ac}}}}\) defined in Methods for the initial damage and the post-repair damage, rescpectively