Table 1 Summary of immunogenicity testing of trastuzumab in laboratory animals and patients’ sera
From: Trastuzumab immunogenicity development in patients’ sera and in laboratory animals
Applied approach | (A) In vivo immunogenicity testing of trastuzumab in lab animals | ||
(B) In vitro detection of anti-trastuzumab Ab levels in patient’s serum samples | |||
Methodology | Approach A | Using one control group and 3 groups injected with different concentrations of trastuzumab. | |
Approach B | Using ACE assay (analysis of serum samples of 101 patients) | ||
1 | Analysis of 18 patient’s serum samples withdrawn before trastuzumab treatment course | ||
2 | Analysis of 46 patient’s serum samples withdrawn at a single point during trastuzumab treatment course | ||
3 | Analysis of serum samples of 32 patients withdrawn at 2 different points during trastuzumab treatment course | ||
4 | Analysis of 5 patient’s serum samples withdrawn after trastuzumab treatment course | ||
Using MTT cytotoxicity assay | |||
Determination of neutralizing activity of anti-trastuzumab Ab in a single patient’s serum sample that showed highest ADA titer | |||
Results | Approach A | Results are presented in Fig. 1 - Trastuzumab showed low immunogenicity in mice since the anti-trastuzumab Ab levels developed in tested groups injected with the drug didn’t exceed 1.3 | |
Approach B | Using ACE assay (analysis of serum samples of 101 patients) | ||
1 | - Only 3 serum samples showed anti-trastuzumab Ab titers between 0.7–0.8 while the rest samples showed no detected anti-trastuzumab Ab | ||
2 | Results are presented in Table 2 - 30 samples showed no detected anti-trastuzumab Ab while the remaining 16 samples showed variable levels of anti-trastuzumab Ab titers ranging from 1.07–8.18. | ||
3 | Results are presented in Table 3 - at the 1st assay point 16 out of 32 tested samples showed variable levels of anti-trastuzumab Ab ranging from 1.13–4.64, while at the 2nd assay point only 9 out of 32 tested samples showed variable levels of anti-trastuzumab Ab ranging from 1.01–2.4 | ||
4 | Results are presented in Table 4 -Only two serum samples coded T3–99 and T3–100 of two patients showed elevated levels of ADAs of 103.63 and 7.13, respectively. The patient of the serum sample coded T3–99 didn’t complete the 17 doses of trastuzumab treatment course as she didn’t respond clinically to treatment. She only received 2 doses of trastuzumab | ||
Using MTT cytotoxicity assay | |||
Results are presented in Table 5 - the neutralization of trastuzumab activity was observed when: 1- the drug and serum preparations were added simultaneously to MCF-7 cell line 2- the serum preparations were added to MCF-7 cell line one hour before drug addition | |||