Potential cost savings by dose down-rounding of monoclonal antibodies in a community cancer center

Purpose Increasing new cancer cases and approval of effective but expensive new drugs extending survival have led to unsustainable cancer care costs. Potential cost savings by a hypothetical dose down-rounding project of monoclonal antibodies at a community-based cancer center is presented. Methods From October 2014 through October 2015, metastatic cancer patients receiving monoclonal antibodies at CHI-Health St Francis Cancer Treatment Center in Grand Island, Nebraska, were identified through electronic health records. A total of 11 different types of monoclonal antibodies that were administered during the study period were identified. Trastuzumab, ofatumumab, and obinutuzumab did not require dose-rounding; thus, they were excluded from the analyses. Available vial size(s) and costs per milligram per average wholesale price for each monoclonal antibody were recorded. Costs of actual amounts prescribed were compared to the costs of theoretically reduced ≤5% and ≤10% doses rounded to the nearest vial sizes. Reduced doses resulting in a decreased number of opened vials qualified for meaningful dose down-rounding and were included in the analysis. Average actual dose reduction percentage resulting in cost savings for both groups was also calculated. Results A total of 728 doses of eight monoclonal antibodies suitable for dose down-rounding were identified. Vial sizes of pembrolizumab and ipilimumab did not allow for a meaningful dose down-rounding. At the ≤5% dose down-rounding, 255 of 728 doses (35%) qualified with a potential annual cost savings of $220,793.80. At the ≤10% dose down-rounding, 526 of 728 doses (72%) qualified with a potential annual cost savings of $454,461.00. The average actual dose reduction was 2.4% for the ≤5% dose reduction group and 4.9% for the ≤10% dose reduction group. Overall average cost savings per qualifying dose reduction was around $865.00. More doses qualified for cost savings in the ≤10% dose reduction group. Significant differences between different monoclonal antibodies for dose rounding at either ≤5% (p = 0.002) or ≤10% (p < 0.001) were observed. Conclusion A practical dose down-rounding procedure may allow significant cost reduction in metastatic cancer setting, where the cure is not the goal. Drug waste can be avoided by convenient vial sizes or can even be eliminated by lyophilized forms like in trastuzumab. Our data reflect the monoclonal antibody use and potential cost savings with the proposed dose down-rounding approach in a community-based cancer program.

Specific immunization using keyhole limpet hemocyanin-ganglioside conjugates

In a search for adjuvants of non-bacterial origin for immunization with ganglioside, we investigated whether chemical coupling to immune stimulatory protein could increase the immunogenicity of sialoglycosphingolipid. A novel method for the linkage of glycosphingolipids, including gangliosides, to protein was established. The procedure includes lysis of the sphingoid double bond by ozone, reduction of the ozonolysis product to the aldehyde, and coupling to amino groups, either directly by reductamination, or by conjugation via a long aliphatic chain dicarboxylic acid linker. Using this method, gangliosides Gfpt1 (IV2-Fuc-, II3NeuAc-Gg4Cer), Glac2 [II3(NeuAc)2-LacCer], and Gtet1 (II3NeuAc-Gg4Cer) were coupled to keyhole limpet hemocyanin (KLH), and the immunogenicity of the conjugates was tested. Immunization of mice with the KLH-ganglioside conjugates led in each case to the formation of IgG- and IgM antibodies that recognized the underivatized gangliosides, respectively. In contrast to this, mixtures of KLH and ganglioside proved ineffective for immunization. KLH-tumor-associated ganglioside conjugates may, therefore, be considered as possible vaccines in immune therapy of cancer.

Re-assessment of acidic glycosphingolipids in small-cell-lung-cancer tissues and cell lines

The occurrence of tumor-associated glycosphingolipids (GSLs) has been documented in a variety of cancer tissues (Hakomori, 1984, 1985, 1989). In the case of small-cell lung cancer (SCLC), the monosialoganglioside IV2Fuc-II3NeuAc-Gg4Cer (Fuc-GM1; short notations of gangliosides are according to Svennerholm, 1963), first described from bovine liver (Wiegandt, 1973), was found to be a unique tumor-associated GSL (Nilsson et al., 1984). It is present in up to 90% of all SCLC cases as compared with 25% frequency in non-SCLC, and no occurrence in normal lung (Brezicka et al., 1989, 1992). Thus, Fuc-GM1 may represent a suitable target antigen for immunotherapy of SCLC, and successful experiments have been performed showing tumor-cell killing by monoclonal antibodies (MAbs) against Fuc-GM1, both in vitro and, in a mouse model, in vivo (Brezicka et al., 1991). However, an effective tumor vaccination in humans would require this antigen to be expressed by the primary tumor and also by all metastases. The co-expression of Fuc-GM1 has already been reported in primary tumors and in most but not all metastases of SCLC (Hanquing et al., 1986; Nilsson et al., 1986; Brezicka et al., 1989). In view of the significance this ganglioside may have for possible immunotherapeutical approaches to SCLC and of the difficulty in obtaining a sufficient number of samples for analysis, a re-assessment of Fuc-GM1 expression was made in SCLC primary tumors and their metastases, as well as in established SCLC cell lines. In addition, the possible presence of such gangliosides, that might help to explain the selective tetanus-toxin binding of SCLC cells (Critchley et al., 1986; Heymanns et al., 1989) was investigated. Finally, the typical occurrence of sulfatide in all SCLC tissues and cell lines could be established.