Interim analysis of the use of the anti-idiotype breast cancer vaccine 11D10 (TriAb) in conjunction with autologous stem cell transplantation in patients with metastatic breast cancer

Anti-idiotypic antibodies as cancer vaccines: achievements and future improvements

Since the discovery of tumor-associated antigens (TAAs), researchers have tried to develop immune-based anti-cancer therapies. Thanks to their specificity, monoclonal antibodies (mAbs) offer the major advantage to induce fewer side effects than those caused by non-specific conventional treatments (e.g., chemotherapy, radiotherapy). Passive immunotherapy by means of mAbs or cytokines has proved efficacy in oncology and validated the use of immune-based agents as part of anti-cancer treatment options. The next step was to try to induce an active immune protection aiming to boost own’s host immune defense against TAAs. Cancer vaccines are thus developed to specifically induce active immune protection targeting only tumor cells while preserving normal tissues from a non-specific toxicity. But, as most of TAAs are self antigens, an immune tolerance against them exists representing a barrier to effective vaccination against these oncoproteins. One promising approach to break this immune tolerance consists in the use of anti-idiotypic (anti-Id) mAbs, so called Ab2, as antigen surrogates. This vaccination strategy allows also immunization against non-proteic antigens (such as carbohydrates). In some clinical studies, anti-Id cancer vaccines indeed induced efficient humoral and/or cellular immune responses associated with clinical benefit. This review article will focus on recent achievements of anti-Id mAbs use as cancer vaccines in solid tumors.

Fetal and Neonatal Illnesses Caused or Influenced by Maternal Transplacental IgG and/or Therapeutic Antibodies Applied During Pregnancy

The human fetus is protected by the mother’s antibodies. At the end of the pregnancy, the concentration of maternal antibodies is higher in the cord blood, than in the maternal circulation. Simultaneously, the immune system of the fetus begins to work and from the second trimester, fetal IgM is produced by the fetal immune system specific to microorganisms and antigens passing the maternal-fetal barrier. The same time the fetal immune system has to cope and develop tolerance and T_REG cells to the maternal microchimeric cells, latent virus-carrier maternal cells and microorganisms transported through the maternal-fetal barrier.

The maternal phenotypic inheritance may hide risks for the newborn, too. Antibody mediated enhancement results in dengue shock syndrome in the first 8 month of age of the baby.

A series of pathologic maternal antibodies may elicit neonatal illnesses upon birth usually recovering during the first months of the life of the offspring. Certain antibodies, however, may impair the fetal or neonatal tissues or organs resulting prolonged recovery or initiating prolonged pathological processes of the children.

The importance of maternal anti-idiotypic antibodies are believed to prime the fetal immune system with epitopes of etiologic agents infected the mother during her whole life before pregnancy and delivery.

The chemotherapeutical and biological substances used for the therapy of the mother will be transcytosed into the fetal body during the last two trimesters of pregnancy. The long series of the therapeutic monoclonal antibodies and conjugates has not been tested systematically yet. The available data are summarised in this chapter.

The innate immunity plays an important role in fetal defence. The concentration of interferon is relative high in the placenta. This is probably one reason, why the therapeutic interferon treatment of the mother does not impair the fetal development.

Anti-idiotype antibodies in cancer treatment

As a cancer immunotherapy tool, idiotypes (Ids) have been used in different ways over the last three decades, depending on the actual human tumor cell target. It all started with passive, monoclonal, anti-Id antibody treatment of B-cell lymphoma, a setting in which results were tantalizing, but logistics unsustainable. It then moved toward the development of anti-Id vaccines for the treatment of the same tumors, a setting in which we have recently provided the first formal proof of principle of clinical benefit associated with the use of a human cancer vaccine. Meanwhile, it also expanded in the direction of exploiting the antigenic mimicry of some Ids with Id-unrelated, tumor-associated antigens for the immunotherapy of a number of solid tumors, a setting in which clinical results are still far from being consolidated. All in all, over the years Id-based immunotherapy has paved the way for a number of seminal therapeutic improvements for cancer patients, including the development of most if not all Id-unrelated monoclonal antibodies that have recently revolutionized the field.

The role of new targeted therapies in small-cell lung cancer

Lung cancer is the leading world-wide cause of cancer death. Small-cell lung cancer (SCLC) accounts for 20-25% of lung carcinomas. Chemotherapy is the cornerstone of treatment of SCLC. In limited disease, median survival is about 12-16 months with 4-5% of long-term survivors, in extensive disease median survival is 7-11 months. Improving the survival rate of patients with SCLC requires a better understanding of tumour biology and the subsequent development of novel therapeutic strategies. Several targeted agents have been introduced into clinical trials in SCLC and some phase III studies have already produced definitive results. Currently, the minority of these new agents offers a promise of improved outcomes, and negative results are more commonly reported than positive ones. To date, no targeted therapy has been approved for use in the treatment of patients with SCLC. This review will focus on the main novel biologic agents investigated in the treatment of SCLC.

Ongoing and future trials of biologic therapies in lung cancer

Lung cancer is the leading world-wide cause of cancer death. The care rate remains less than 15% despite improvements in surgery, radiotherapy and chemotherapy. The majority of deaths can be attributed to systemic metastases. Chemotherapy prolongs survival but produces few complete responses and survival at 5-years is rare. Molecular advances have provided many new targets for lung cancer therapy. Many new agents have been developed to attack these targets. This article describes current and proposed trials for these new targeted therapies in both small cell and non-small cell lung cancers.

Should we continue to study high-dose chemotherapy in metastatic breast cancer patients? A critical review of the published data

Data from eight randomised trials on high-dose chemotherapy (HDC) for metastatic breast cancer (MBC) have been published, but only seven studies are evaluable after the Bezwoda trial was discredited. Moreover, overall survival (OS) has been evaluated in only four out of seven studies since three had a crossover design. OS was similar for the HDC and standard-dose chemotherapy (SDC) group in the four evaluable trials, while disease-free survival (DFS) was improved in the HDC group in six of the seven trials. The delay in relapse for patients with metastatic disease represents an important clinical outcome; furthermore, since none of the reported studies randomised more than 220 patients, their statistical power may have been too limited to detect meaningful survival differences. Finally, preliminary experiences have shown that HDC seems to be the ideal platform upon which to build novel therapies. In conclusion, HDC remains an important field of clinical research for breast cancer patients with stage IV disease and, from the studies reported in this article, there is some evidence for offering this therapeutic modality to selected patients who are interested in a medically aggressive approach.

Use of the anti-idiotype breast cancer vaccine 11D10 in conjunction with autologous stem cell transplantation in patients with metastatic breast cancer

The results of cytotoxic therapy, including dose-intensive therapy requiring autologous stem cell transplantation (ASCT), have been disappointing in patients with metastatic breast cancer, as almost all patients eventually experience disease progression. There has been a renewed interest in immunotherapeutic strategies in this disease, including evaluation of several breast cancer vaccines. In the current study, we describe the results of a program in which the anti-idiotype breast cancer vaccine 11D10 (TriAb) was administered before and after ASCT in patients with metastatic breast cancer chemosensitive to previous conventional therapy. The toxicity of this approach was acceptable, and idiotype-specific humoral and T-cell proliferative responses were observed in the majority of patients within a few weeks post-ASCT. The actuarial 3-year overall survival rate was 48% (95% CI, 32%-64%), while the progression-free survival rate was 32% (95% CI, 19%-45%). Multivariate analysis identified achievement of a strong antibody and cellular immune response to the vaccine as the only significant prognostic factors for outcome. The ability to reliably produce robust immune responses after ASCT is encouraging. Further studies are required to determine if the immune response mediates an antitumor benefit in these patients.