Introduction

Background

Integrative medicine is used in up to 70% of adult oncology cases [1] and up to a third of pediatric oncology patients in Germany have been found to use some form of integrative therapy during cancer treatment [2]. Of pediatric patients in oncological treatment who also use integrative therapy, a broad survey with users found that anthroposophic supportive treatment (AST) was used by a third of patients in German pediatric oncological units [3]. Deriving from an alternative-holistic medical tradition developed by Steiner and Wegman in the 1920s that is well-established in Germany and in Europe, anthroposophic medicinal products (AMP) are used in cancer treatment for symptom management, to achieve a stable condition, to improve the tolerability of standard chemotherapy and improve the quality of life (QoL) [4]. AMP in pediatric oncology consist of a range of plant and animal-based tinctures, globules, extracts, injections, and compresses [3]. Mistletoe, given in oral and injectable form, is the most frequently used AMP in oncology and has demonstrated some benefit [5, 6]. Despite a century of AST for oncological patients such as mistletoe, the effect of treatments given in conjunction with standard chemotherapy is not well-studied in oncology and even less so in pediatric oncology. Evaluated exceptions have shown that in particular, children may benefit from AST interventions [3, 7]. The small body of research that does exist in pediatric oncology using AST has featured case studies highlighting safety [8,9,10] and quality of life for the young person [11, 12] rather than results of planned clinical trials. Parents of children suffering from intensive chemotherapy view AST as a possible means of assisting their child through difficult circumstances, but at the same time, the potential side effects of AST necessitate better monitoring clinical trials [2, 13]. This study is the first randomized controlled trial in pediatric oncology to systematically compare the toxicity of chemotherapy and survival in a 5-year follow up with or without an add-on AST intervention during intensive chemotherapy.

Objective and hypothesis including 5-year follow up data

This study investigated the influence of the AST concept on the chemotherapy-associated toxicity in a randomized clinical trial undertaken at 12 German pediatric oncology clinics. The trial, consisting of an AST intervention, compared an application of AMP in pediatric oncology patients aged 1–18 undergoing standard chemotherapy to the control without AMP. A base of 8 AMP plus 11 on-demand, indication-related on-demand AMP were administered in the intervention group during the intensive chemotherapy phase. The trial tested the hypothesis that the AST would reduce the toxicity sum score for pediatric oncology patients undergoing standard treatment. The study documented long term changes with 5-year follow up data. The trial’s primary objective investigated the influence of the AST on the chemotherapy-associated toxicity measured by means of a toxicity sum score for hematology, mucositis, general condition and infection using NCI-CTC scales and the overall safety in terms of overall survival (OS) and event-free survival (EFS) until the end of the 5-year follow up. The secondary objective of the study was to investigate any decrease in chemotherapy-associated toxicity.

Methods

Trial design

This clinical trial investigated the effect of the AST for children undergoing chemotherapy combined with standard clinical care from 2005 to 2013 at 12 tertiary-level pediatric care units throughout Germany in a prospective, open-label, individually-randomized, controlled, national clinical study with parallel group design (Table 1: Inclusion & Exclusion Criteria Anthroposophic Supportive Therapy Study). The Institutional Review Board of Charité - Universitätsmedizin Berlin approved the trial as the responsible ethics committee (EA2/141/05). The study was registered at the European Union (EU) Drug Clinical Trials Register (EudraCT- No: 2004–002711-83) [14] before its commencement. All participants provided written informed consent in accordance to the Declaration of Helsinki [15].

Table 1 Inclusion & exclusion criteria anthroposophic supportive therapy study

Three approved amendments were made to the original study protocol after commencement of the study and registered once the need for changes became apparent. These included necessary changes made to the inclusion of new and updated chemotherapy protocols, essential adjustments to administered treatments, necessary revision of study administration and modifications to inclusion/exclusion specifications.

Study recruitment

Patients aged 1–18 with planned chemotherapy with a histologically and/or immunologically confirmed pediatric malignancy according to the current standardized treatment protocol were regarded eligible for trial recruitment and recruited from one of the 12 participating tertiary pediatric oncology units if the written consent was given. At the baseline, age, gender, educational background and familial situation was recorded for both groups. Sample size was determined based on the intention to decrease the NCI-CTC scale sum score of 2.1 obtained in the ALL-BFM-2000 study [16] by a clinically important difference of 10% to 1.9 in the intervention group (SD = 0.6, alpha = 0.05, Power = 80%).

Study intervention

Patients of the intervention group only were given the AST regimen as an add-on therapy to standard chemotherapy treatment (see Fig. 1: Trial Design for the Pediatric Anthroposophic Supportive Treatment).

Fig. 1
figure 1

Trial design for the pediatric anthroposophic supportive treatment

The AST consisted of base AMP including Helixor®, and on-demand supplementary AMP given as needed for symptoms (summary in Table 2: Anthroposophic Supportive Treatment Base Medicinal Products and Supplementary Table). The control group received standard chemotherapy treatment without additional measures. Administration of the AST intervention and chemotherapy protocol were tailored for each type of pediatric malignancy included in the trial. This included both the base and the on-demand AMP, which were administered based on acute symptoms during intensive chemotherapy. The intervention group started the AST between the day of randomization and day 10 of the first chemotherapy cycle.

Table 2 Anthroposophic supportive treatment base medicinal products

Study randomization

Randomization was centrally allocated at the study headquarters (Charité) by trial administrators (GS, CHH) into intervention and control group by a computer supported standard operating procedure that used a combination of unique code identifier and abbreviation for the chemotherapy treatment.

Results

Sample description

A total of 556 patients were screened for eligibility at the 12 trial sites between September 2005 and November 2013 (cf. Fig. 2: Anthroposophic Supportive Treatment Trial Consort Chart). Of these, 340 were found eligible, sorted into their diagnosis groups and then randomized. Reasons for ineligibility in the study were often due to necessary expediency of treatment or complexity of individual clinical cases that complicated study inclusion. After accounting for 52 (31 intervention, 21 control) dropouts, 288 patients were included in the intention-to-treat analysis (ITT), of which 216 patients completed all observational visits and administered at least 75% of the base study medications and could thus be included also in the per-protocol analysis (PP).

Fig. 2
figure 2

Anthroposophic supportive treatment trial consort chart

Demographic and clinical parameters of the patient groups can be found in Table 3: Baseline Characteristics. Baseline age, gender, educational background and familial situation in both groups were similar: About 62% of patients were male, average age in the intervention group was 8 years, while averaged 7.5 years in the control. The intervention group bodyweight averaged 35 kg and 32 kg in the control.

Table 3 Baseline characteristics

Patients suffering from an acute lymphoblastic leukemia (ALL) by far made up for the largest group with approximately 54% (154 / 288 ITT and 117 / 216 PP patients). Only a minor fraction had previous illnesses (< 15%).

Primary outcome: the toxicity sum score (TSS)

The underlying data for the custom-defined Toxicity Sum Score (TSS) was available for 279 of the 288 ITT (96.9%) and for 208 of the 216 PP patients (96.3%). In the ITT analysis, the mean TSS was slightly higher in the intervention group (12.1 ± 3.92, median = 11.6) than in the control group (11.8 ± 4.54, median = 10.9), but slightly lower in the PP analysis (11.4 ± 3.58, median = 11.4 in the intervention group vs. 11.5 ± 4.33, median = 10.7 in the control group). Neither of these differences became statistically significant in the Mann-Whitney-U-Test, with p = 0.257 and p = 0.716 for the ITT and PP analysis, respectively (Fig. 3: Toxicity Sum Score (TSS) Primary Outcome).

Fig. 3
figure 3

Toxicity Sum Score (TSS) primary outcome

Secondary outcome: determination of chemotherapy-associated toxicity

Analysis of 43 additional toxicity criteria on the effect of AMP on other chemotherapy-related toxicity found a statistically significant reduction in number of diarrhea episodes in the intervention group (ITT p = 0.054; Mann-Whitney-U-test and PP- intervention group with p = 0.044, Mann-Whitney-U-test). However, there was no statistical significance for any other secondary outcome toxicity parameter in either the ITT or PP population.

Adverse events

Adverse events were only recorded, and thus only analyzed, for the patients in the intervention group (initially 170 patients) who had self-administered at least one of the AMPs during the observational period (n = 163). All in all, 607 AE were documented in 123 patients, among them 532 (87.6%) with secured (n = 472), probable (n = 7), possible (n = 49) or undecidable (n = 4) causal relationship to the treatments.

The majority of the cases with secured causality, i.e. 447 cases observed in 105 patients, were accounted for by local inflammations at the injection site after subcutaneous administration of Helixor® A with a diameter of 5 cm and more. While local reactions from 2 to 5 cm in diameter are expected and even desired in mistletoe therapy, reactions with diameters of more than 5 cm are regarded as AE by the study protocol and thus documented. All other AE were related to the remaining products and were only observed in single cases.

Serious adverse events

In contrast to AE, Serious Adverse Events SAE were recorded for the intervention and the control group. In total, 15 SAE in 11 patients were recorded for the main study period. Thorough evaluation by the study management and the Data and Safety Monitoring Committee (DSMC) showed that all SAE were related to chemotherapy-associated toxicities and not to the additional AST and were thus assessed as mislabeled records in the sense of the study protocol. Three of the misrepresented SAE had a lethal outcome with sepsis. Two were in the intervention group: one with fulminant sepsis with lethal outcome and the other with fulminant sepsis with absolute neutropenia and presumption diagnosis of intestinal perforation; these had no determined causal relationship with the intervention study medication. The third SAE occurred in the control group. According to the assessment of the study management, the cause for these SAE stemmed from the chemotherapy with which these patients were treated.

Outcome of five-year follow up on event-free and overall survival & safety

Overall survival rates (OS) and events-free survival rates (EFS) were based on the intention-to-treat population (288 patients). For the analysis, data of patients in 12 groups with comparable chemotherapy were evaluated (upper half of Fig. 2). None of them showed a statistically significant difference according to the log-rank test, when Bonferroni correction was applied for multiple testing (alpha* = 0.0045). In the remaining six groups (ALL others, COALL Non-HR, Non-Hodgkin-Lymphoma, glioblastoma, germ cell tumor, nephroblastoma), no survival data analysis (log-rank test) could be applied because only one or no patient had died in the group.

Event-free survival rates (EFS) did not reveal any statistically significant differences between the two groups (lower half of Table 4).

Table 4 Secondary outcomes chemotherapy-associated toxicity parameter list

Discussion

This randomized controlled clinical trial investigated the efficacy and safety of an anthroposophic supportive therapy concept consisting of 19 investigational medicinal products, applied as a base and on-demand therapy in addition to standard chemotherapy treatment in children with cancer. For the primary efficacy parameter, the toxicity sum score found no advantage for administration of the anthroposophic supportive therapy that could be demonstrated. Further NCI-CTC toxicity index scores to analyze secondary efficacy parameters only showed an advantage for the administration of the supportive therapy in the reduction of the toxicity index score for diarrhea in the PP-population. In the long term follow up, the explorative analysis of the data available for the 5-year follow up found no indications that efficacy of chemotherapy was influenced by AST. For long-term toxicities there were also no indications of an influence of AST. The AST-concept can be considered as safe in the long-term observation.

Trial findings confirmed that AST was able to be safely administered in a clinical setting. Overall, the analysis of AE including clinical experiences did not reveal any evidence of safety concerns with respect to the administration of the anthroposophic supportive therapy. Additionally, results of this study found no concerns of the compatibility of anthroposophic supportive therapy with the chemotherapy. This study demonstrated that the administration of the anthroposophic supportive therapy did not disrupt or delay therapy application in the intervention group, which is a crucial precondition for effective administration of chemotherapy.

This study showed the feasibility of conducting a high-quality, digitally-centralized randomized, scientific evaluation of an integrative therapy at multiple centers in the pediatric oncology setting. To our knowledge, there has only been one published comparable randomized study of an integrative therapy in pediatric oncology [17]. A strength of this first randomized controlled trial of a complementary anthroposophic treatment to be conducted within pediatric oncology demonstrated the safety of the intervention, the most critical overall outcome. This is comparable to findings in other randomized studies with adults [18, 19]. Additionally, the trial was conducted with a high methodological standard with centralized digital data management and inclusion of multiple centers, and provided long term follow up of the intervention effects.

Limitations

Limitations, however, should also be mentioned. The complexity of the range of base and on-demand AMP necessitated clearer application guidelines at the study outset that may have permitted more extensive use in symptom treatment. This, on the other hand was difficult to tailor to individual participant tumor entities given the heterogeneity of malignancies included in the trial.

While other studies have reached the conclusion of a weak evidence base for single substance efficacy such as with viscum album (mistletoe) given in oncology trials with adults [5], marked quality of life factors have still been found to improve [18, 20]. As one of the success stories in oncology, adjustments to treatment dosages and schedules in pediatric oncology therapy has led simultaneously to an increase of survival and targeted therapeutics with better outcomes and resulting in less toxicity [21, 22]. One possible explanation for a lack in demonstrable gains in toxicity measures is the ceiling effect of targeted treatments and optimized symptom management.

However, studies that systematically research the effects of combined and comprehensive AST have been markedly absent. This study contributes significantly to this data gap whereby integrative treatments such as AST are in demand [7] especially in pediatric oncology. AST and other integrative treatments are often already being given by parents of children suffering from chronic conditions such as cancer in Germany as a possible means of assisting their child through difficult circumstances without specific effects being monitored within clinical trials [2, 13]. A singular known case report has previously raised the possibility of a connection between the promotion of tumor progression of a non-Hodgkin lymphoma at the subcutaneous injection site of viscum album therapy [23]. However, this study makes a strong case, along with other published findings, to demonstrate the safety of mistletoe injections in pediatric oncology [24, 25]. Where other areas of integrative medicine have shown efficacious results [26], facilitating a study design that investigates efficacy of combined AMP has provided an important lesson for the design of future research. Logistical and financial trade-offs must be carefully weighed and caution is needed in expediating hopeful outcomes for pediatric oncology patients, even if potential benefits to the quality of life may exist. While rigorous research is still needed for the application of comprehensive AST, a targeted approach, focusing for instance on one malignancy population or with a mixed-method design would potentially better capture effects of AMP.

Conclusions

This study investigated an anthroposophic supportive therapy concept consisting of 19 medications as add-on therapy to standard treatment in children with cancer. For both the primary target criterion toxicity sum score and secondary target parameters, no advantage of using anthroposophic supportive therapy could be shown in this setting. Considering the previous clinical experience in the study population, it can be assumed that the anthroposophic supportive therapy can be applied safely. A key result is that there was no delay in therapy or reduction in therapy in the intervention group nor a statistical difference in 5-year survival as a result of the use of anthroposophic supportive therapy; an essential precondition for effective application of chemotherapy. Notable methodological and logistical lessons were demonstrated about the application of a supportive therapy concept in pediatric oncology that has important transferability for future research.