Loading doses for costly cancer biologicals: a cause for concern or tilting at windmills?

The emergence of novel, effective but expensive biological therapies is significantly improving outcomes for many patients with cancer, but also substantially increasing treatment costs. Monoclonal antibodies with long half-lives have often been developed using loading doses to hasten the achievement of a therapeutic dose. Although the benefits of loading doses have not been proven, we caution against abandoning this practice on uncertain theoretical grounds. Rather, the issue of loading doses should be seen in the broader context of how best to define the optimal dose, schedule and duration of treatment through novel clinical trial designs.

Developing an integrated rehabilitation model for thoracic cancer services: views of patients, informal carers and clinicians.

BACKGROUND: Access to rehabilitation to prevent disability and optimise function is recommended for patients with cancer, including following cancer diagnosis. Models to integrate rehabilitation within oncology services as cancer treatment commences are required, but must be informed by those they are intended to support. We aimed to identify views of patients, carers and clinicians to develop and refine a rehabilitation model to be tested in a feasibility trial for people newly diagnosed with lung cancer or mesothelioma. METHODS: We conducted a focus group study with people affected by lung cancer or mesothelioma, their carers and clinicians providing their care to identify priorities for rehabilitation in this period. We sought views on core intervention components, processes and outcomes and integration with oncology services. Data were analysed using thematic analysis. RESULTS: Fifteen clinicians (oncologists, nurse specialists, physiotherapists and occupational therapists), nine patients and five carers participated. A proposed outline rehabilitation model was perceived as highly relevant for this population. Participants recommended prompt and brief rehabilitation input, delivered whilst people attend for hospital appointments or at home to maximise accessibility and acceptability. Participants recognised variation in need and all prioritised tailored support for symptom self-management, daily activities and the involvement of carers. Clinicians also prioritised achieving fitness for oncology treatment. Patients and carers prioritised a sensitive manner of approach, positivity and giving hope for the future. Participant's recommendations for outcome measurement related to confidence in usual daily activities, symptom control and oncology treatment completion rates over objective measures of cardiorespiratory fitness. CONCLUSION: The importance of providing tailored rehabilitation around the time of diagnosis for people with lung cancer or mesothelioma was affirmed by all participants. The refined model of rehabilitation recommended for testing in a feasibility trial is flexible, tailored and short-term. It aims to support people to self-manage symptoms, tolerate cancer treatments and to remain active and independent in daily life. It is delivered alongside scheduled hospital appointments or at home by an expert practitioner sensitive to the psycho-social sequelae that follow a diagnosis of thoracic cancer.

Salvage Chemotherapy With Gemcitabine, Paclitaxel, Ifosfamide, and Cisplatin for Relapsed Germ Cell Cancer.

BACKGROUND: Metastatic germ cell tumors remain potentially curable when treated with salvage chemotherapy at first relapse. In the present phase I/II study, we sought to improve on the response rate and duration of the TIP (paclitaxel, ifosfamide, cisplatin) regimen by adding gemcitabine (Gem-TIP). MATERIALS AND METHODS: Twenty patients were recruited after failure of first-line cisplatin-containing chemotherapy. The primary objectives were to determine the maximum tolerated dose of gemcitabine when combined with TIP and to establish the dose intensity of the TIP drugs in this combination. The secondary objectives were the response rates, failure-free survival, and overall survival. RESULTS: The maximum tolerated dose of gemcitabine was 1200 mg/m2. The mean relative dose intensity was 95% (95% confidence interval [CI], 90.2%-99.2%) for gemcitabine, 96% (95% CI, 92.9%-98.7%) for paclitaxel, 92% (95% CI, 84.5%-98.8%) for ifosfamide, and 94% (95% CI, 89.3%-99.0%) for cisplatin. The overall complete response rate was 50%; another 30% of the patients achieved a partial response. The 1-year failure-free survival and overall survival rates were 68% (95% CI, 43%-84%) and 89.5% (95% CI, 64%-97%), respectively. CONCLUSION: Gemcitabine can be added to TIP chemotherapy at the full dose, with manageable toxicity and no detrimental effect on the dose intensity of the TIP drugs. The response rate and duration were improved compared with those reported from the Medical Research Council TIP trial; further evaluation is warranted.

Oral administration of cannabis with lipids leads to high levels of cannabinoids in the intestinal lymphatic system and prominent immunomodulation.

Cannabidiol (CBD) and ∆9-tetrahydrocannabinol (THC) have well documented immunomodulatory effects in vitro, but not following oral administration in humans. Here we show that oral co-administration of cannabinoids with lipids can substantially increase their intestinal lymphatic transport in rats. CBD concentrations in the lymph were 250-fold higher than in plasma, while THC concentrations in the lymph were 100-fold higher than in plasma. Since cannabinoids are currently in clinical use for the treatment of spasticity in multiple sclerosis (MS) patients and to alleviate nausea and vomiting associated with chemotherapy in cancer patients, lymphocytes from those patients were used to assess the immunomodulatory effects of cannabinoids. The levels of cannabinoids recovered in the intestinal lymphatic system, but not in plasma, were substantially above the immunomodulatory threshold in murine and human lymphocytes. CBD showed higher immunosuppressive effects than THC. Moreover, immune cells from MS patients were more susceptible to the immunosuppressive effects of cannabinoids than those from healthy volunteers or cancer patients. Therefore, administering cannabinoids with a high-fat meal or in lipid-based formulations has the potential to be a therapeutic approach to improve the treatment of MS, or indeed other autoimmune disorders. However, intestinal lymphatic transport of cannabinoids in immunocompromised patients requires caution.

Dietary fats and pharmaceutical lipid excipients increase systemic exposure to orally administered cannabis and cannabis-based medicines.

There has been an escalating interest in the medicinal use of Cannabis sativa in recent years. Cannabis is often administered orally with fat-containing foods, or in lipid-based pharmaceutical preparations. However, the impact of lipids on the exposure of patients to cannabis components has not been explored. Therefore, the aim of this study is to elucidate the effect of oral co-administration of lipids on the exposure to two main active cannabinoids, Δ(9)-tetrahydrocannabinol (THC) and cannabidiol (CBD). In this study, oral co-administration of lipids enhanced the systemic exposure of rats to THC and CBD by 2.5-fold and 3-fold, respectively, compared to lipid-free formulations. In vitro lipolysis was conducted to explore the effect of lipids on the intestinal solubilisation of cannabinoids. More than 30% of THC and CBD were distributed into micellar fraction following lipolysis, suggesting that at least one-third of the administered dose will be available for absorption following co-administration with lipids. Both cannabinoids showed very high affinity for artificial CM-like particles, as well as for rat and human CM, suggesting high potential for intestinal lymphatic transport. Moreover, comparable affinity of cannabinoids for rat and human CM suggests that similar increased exposure effects may be expected in humans. In conclusion, co-administration of dietary lipids or pharmaceutical lipid excipients has the potential to substantially increase the exposure to orally administered cannabis and cannabis-based medicines. The increase in patient exposure to cannabinoids is of high clinical importance as it could affect the therapeutic effect, but also toxicity, of orally administered cannabis or cannabis-based medicines.

Severe sequence-specific toxicity when capecitabine is given after Fluorouracil and leucovorin.

PURPOSE: Options for single-agent fluoropyrimidine adjuvant therapy after bowel cancer resection include intravenous fluorouracil with leucovorin (FU/LV) or oral capecitabine. These treatments have similar efficacy but differ in convenience and toxicity. We therefore wished to compare their overall acceptability to patients. PATIENTS AND METHODS: Patients scheduled for adjuvant single-agent fluoropyrimidine therapy were randomly assigned to receive once-weekly FU/LV (425 mg/m(2) FU, 45 mg LV) for 6 weeks, followed by two 3-week cycles of capecitabine (1,250 mg/m(2) twice daily, days 1 through 14), or the same treatments but in reverse order. After 12 weeks, the patients were asked which treatment they preferred, and received the preferred treatment for an additional 12 weeks. The primary end point was patient preference. RESULTS: After 40 of the planned 74 patients had been randomly assigned, real-time adverse event monitoring led to early trial closure because of excess sequence-specific toxicity. Eleven of 14 patients (79%) receiving capecitabine as their second treatment experienced grade >/= 3 toxicity. This compared with five of 18 patients (28%) receiving capecitabine as the first treatment, and no patients receiving FU/LV as the first treatment (zero of 16) or the second treatment (zero of 12). Similar imbalances were seen in the proportion of patients requiring interruption of treatment. CONCLUSION: In chemotherapy-naïve patients, capecitabine produced more toxicity than FU/LV, but at levels in line with previously reported data. However, treatment with capecitabine after FU/LV caused markedly increased toxicity, indicating a sequence-specific interaction. The mechanism has not been determined, but interaction with intracellularly retained folate after FU/LV therapy is a possibility. Oncologists need to be aware of this risk if considering crossing patients over from FU/LV to capecitabine-based regimens.