Israel Medical Association Journal

Background: The use of proprotein convertase subtilisin/kexin type 9 monoclonal antibodies (PCSK9 mAbs) is emerging for lowering low-density lipoprotein cholesterol (LDL-C). However, real-world data is lacking for their use among elderly patients.

Objective: To define the characteristics of elderly patients treated with PCSK9 mAbs and to evaluate the efficacy and tolerability compared with younger patients.

Methods: We conducted a retrospective cohort study of elderly patients (≥ 75 years at enrollment) treated with PCSK9 mAbs for primary and secondary cardiovascular prevention. Data were retrieved for demographic and clinical characteristics; indications for treatment; agents and dosages; concomitant lipid lowering treatment; LDL-C levels at baseline, 6, 12 months, and at the end of follow up. Data also included achieving LDL-C target levels and adverse effects.

Results: The cohort included 91 elderly patients and 92 younger patients, mean age 75.2 ± 3.76 and 58.9 ± 7.4 years (P < 0.0001). Most patients (82%, 80%) were in high/very high-risk categories. For almost all (98%, 99%), the indication was statin intolerance, with PCSK9 mAb monotherapy the most prevalent regimen. The average follow-up was 38.1 ± 20.5 and 30.9 ± 15.8 months (P = 0.0258). Within 6 months the LDL-C levels were reduced by 57% in the elderly group and by 59% in the control group (P = 0.2371). Only 53% and 57% reached their LDL-C target levels. No clinically significant side effects were documented.

Conclusion: PCSK9 mAbs have similar effects and are well tolerated among elderly patients as in younger patients.

Background: HER2 is an important prognostic and predictive marker in invasive breast cancer. It is currently assessed by immunohistochemistry for protein over-expression and by fluorescence in situ hybridization for gene amplification. The immunohistochemistry-equivocal cases (2+) are currently retested by FISH[1] to determine eligibility for trastuzumab treatment. Retesting by FISH significantly raises the cost of patient management and sometimes delays treatment. The 4B5 is a new, FDA-approved, rabbit monoclonal antibody for HER2 testing.

Objectives: To examine the reliability of 4B5 IHC[2] HER2 testing in cases found to be HER2 status equivocal by CB11 IHC.

Methods: Twenty-eight invasive breast cancer cases, with an equivocal HER2 status by CB11 IHC, were retested by the 4B5 antibody as well as by FISH analysis. The scoring was performed using the same guidelines as HercepTest and was correlated with the FISH ratio. Results: Of the original 28 CB11 clone designated equivocal cases, 14 (50%) showed negative HER2 staining using the 4B5 clone (HercepTest score 0 and 1+). Five cases (18%) proved to be positive (HercepTest score 3+) and 9 cases (32%) remained equivocal (HercepTest score 2+). The corresponding FISH ratio results showed that all 4B5 negative cases were negative by FISH testing, with a negative predictive value of 100% 4 of 5 of the 4B5-positive cases were positive by FISH testing, with a positive predictive value of 80%. One 4B5-positive case was borderline-high (2.2 ratio) by FISH. The correlation between 4B5 IHC and FISH was statistically significant (P = 0.0013) by chi-square test.

Conclusions: Sequential testing by 4B5 IHC could greatly reduce the need for FISH testing in cases considered HER2 equivocal by CB11 IHC.
 

 
[1] FISH = fluorescence in situ hybridization

[2] IHC = immunohistochemistry

Idiotypic analyses of anti-DNA autoantibodies were widely reported a decade ago. More than 100 studies were conducted on one of the main analyzed idiotypes, the 16/6 Id of the anti-ssDNA monoclonal antibody. In this review we summarize current knowledge on the characteristics of the 16/6 Id[1], its link to infection and its target epitopes on other molecules known so far. This includes the modulation of T and B cell responses and gene expression by the 16/6 mAb[2] in vitro and in vivo. We focus on the ability and mechanisms by which this idiotype induces experimental lupus in naïve mice, manifested by autoantibody spread, kidney and brain involvement, and leukopenia associated with enhanced sedimentation rate. We also discuss various therapeutic modalities to treat 16/6 induced lupus in mice.