Roferon-A (interferon alpha 2a) combined with Tigason (etretinate) for treatment of cutaneous T cell lymphomas

Results of a Phase II trial of oral bexarotene (Targretin) combined with interferon alfa-2b (Intron-A) for patients with cutaneous T-cell lymphoma

BACKGROUND

Bexarotene is one of the most active single agents for the treatment of recurring or refractory cutaneous T-cell lymphoma (CTCL). Interferon alfa has also been used for many years as an effective treatment for this disease. The results in recent case reports of the combination of bexarotene and interferon alfa have been promising. Based on more extensive results reported with the combination of other retinoids with interferon alfa, the present study attempted to determine the response rate, response duration, and safety of bexarotene (Targretin capsules, Ligand Pharmaceuticals, San Diego, Calif) alone and then with the addition of interferon alfa-2b (Intron-A, Schering-Plough, Kenilworth, NJ).

METHODS

Patients with biopsy-proven CTCL, TNM stages IB, IIA, IIB-IV, were treated with oral bexarotene 300 mg/m2/day for at least 8 weeks. If a complete response was not seen after 8 weeks, interferon alfa-2b 3 million units (MU) subcutaneously was added, and increased to 5 MU if tolerated, 3 times a week.

RESULTS

A total of 22 patients were enrolled at 5 sites, and 18 patients were assessable for response. Overall response rate for combined bexarotene and interferon alfa was 39% (95% confidence interval [CI]: 17%-64%), including 1 patient with a clinical complete response, 6 patients with partial response, 3 patients with stable disease, and 8 patients with progressive disease. Three partial responses were first noted during the bexarotene-alone phase. Adverse events were generally manageable, and only 1 patient was withdrawn from study for hypertriglyceridemia.

CONCLUSIONS

The addition of interferon alfa-2b did not increase the response rate that would have been expected with bexarotene alone.

Mycosis fungoides and Sezary syndrome: therapeutic approach and outcome in 113 patients

BACKGROUND

Mycosis fungoides (MF) and Sezary syndrome (SS) are the most common forms of cutaneous T-cell lymphoma (CTCL). Various topical and systemic therapeutic alternatives are available, but there is no standard or definite curative treatment regimen. When making a decision about the appropriate treatment modality, the age and compliance of the patient, stage of the disease, treatment accessibility, and previous treatment history should be considered.

AIM

To determine the therapeutic response of patients with MF and SS to different treatment modalities. Patients were evaluated with respect to their clinical and demographic features.

METHODS

One hundred and thirteen patients diagnosed clinically and dermatopathologically with MF and SS between March 1984 and June 2001 were included in the study.

RESULTS

Of the 113 patients studied, 110 had a diagnosis of MF and three had a diagnosis of SS; 101 patients (89.4%) were diagnosed with early stage (IA, IB, IIA) and 12 (10.6%) with late stage (IIB, III, IVA, IVB) disease. The age at diagnosis varied between 12 and 81 years (mean, 45.6+/-15.8 years). Fifty-five (48.7%) patients were male and 58 (51.3%) were female. The duration of the skin lesions varied between 1.5 months and 32 years (mean, 6.1 years). Psoralen plus UVA (PUVA) was the most commonly used initial treatment modality in early stage disease (91%), with a complete remission (CR) rate of 80.4%. With PUVA+interferon-alpha (INF-alpha) treatment, CR was 57% in the early stages and 33.3% in the late stages. For late stage disease, systemic therapies, such as pentostatin, gemcitabine, and fludarabine, alone or in combination with INF-alpha, were preferred. Of the 113 patients, eight (7% of the total and 57.1% of the advanced stage cases) died of MF; 21.4% of the late stage patients showed partial remission and 14.2% showed CR. None of the patients diagnosed with early stage disease died of MF, but two (1.9%) progressed to late stage disease.

CONCLUSIONS

PUVA and PUVA+INF-alpha are effective treatment modalities, especially for early stage MF. Once the disease has progressed, both MF and SS are very resistant to treatment regimens, including chemotherapeutic agents. It is important to diagnose and treat these diseases, especially MF, in the early stages for lasting remission.

Low-dose oral bexarotene in combination with low-dose interferon alfa in the treatment of cutaneous T-cell lymphoma: clinical synergism and possible immunologic mechanisms

BACKGROUND

For nearly 2 decades clinicians have been treating cutaneous T-cell lymphoma (CTCL) with regimens that combine interferon alfa with retinoid compounds. In December 1999 a new retinoid, bexarotene, was approved by the US Food and Drug Administration for the treatment of CTCL. At the manufacturer's recommended dose of bexarotene (300 mg/m(2) of body surface area), it has proven to be a highly effective therapy for all stages of CTCL. Nevertheless, this dose is typically associated with adverse effects including severe hyperlipidemia. Furthermore, there appears to be no standardization of dosing among physicians who treat CTCL.

OBSERVATIONS

We present 3 representative patients, 2 with erythrodermic CTCL and 1 with follicular mycosis fungoides, who experienced the rapid clearing of skin disease while being treated with a combination of low-dose bexarotene and low-dose recombinant interferon alfa.

CONCLUSIONS

Combining low-dose bexarotene with low-dose interferon alfa was well tolerated and led to rapid improvement in our patients. We review the clinical and biologic basis for this approach.

Topical and systemic retinoid therapy for cutaneous T-cell lymphoma

Because curative therapies for CTCL are not yet available, short of TSEB in patients who have early-stage disease and allogeneic bone marrow transplantation in patients who have more advanced disease, the goal of current therapies is to prevent progression of MF and to preserve quality of life. The overall conclusion drawn from the studies reported in the literature, is that retinoids as monotherapy, or in combination with other nonaggressive treatment modalities, represent a low-risk treatment alternative that is especially suitable for controlling early stages of MF and other CTCL. A combination of therapies may be more effective in controlling CTCL as shown with IFN-alpha plus retinoids, and, recently, IFN-alpha with bexarotene and other modalities. For example, isotretinoin, followed by TSEB (for stage I to II disease) or preceded by chemotherapy (for stage II and IV disease) and bexarotene plus PUVA or photopheresis plus IFN, gave overall response rates of 82% and 69% in patients who had MF and SS, respectively. Retinoids as monotherapy may induce complete remissions, but usually these responses are of short duration and relapses are common. Clinical response is not identical to histologic clearance. Even in cases with clinically complete clearance of skin lesions, lymphoid infiltrates persisted, which are most likely the source of recurrences. The new generation of retinoids, the RXR selective agonists like bexarotene, represent a promising approach for refractory or persistent MF that is unresponsive to first-line therapies. Individual differences in response to retinoids may be due to different expression of retinoid receptors, functional polymorphisms in metabolizing retinoids, or resistance to some retinoids. In the future, pharmacogenomic studies are needed to clarify the mechanisms that underlie the differing response rates of patients who have CTCL to retinoids. In addition, new agonists of RAR and RXR, either selective or pan agonists, will become available and will enlarge the spectrum of vitamin A analogs that have antitumoral properties.

Scientific rationale for using high-dose multiple micronutrients as an adjunct to standard and experimental cancer therapies

We have hypothesized that high-dose multiple micronutrients, including antioxidants, as an adjunct to standard (radiation therapy and chemotherapy) or experimental therapy (hyperthermia and immunotherapy), may improve the efficacy of cancer therapy by increasing tumor response and decreasing toxicity. Several in vitro studies and some in vivo investigations support this hypothesis. A second hypothesis is that antioxidants may interfere with the efficacy of radiation therapy and chemotherapy. This hypothesis is based on the concept that antioxidants will destroy free radicals that are generated during therapy, thereby protecting cancer cells against death. None of the published data on the effect of antioxidants in combination with radiation or chemotherapeutic agents on tumor cells supports the second hypothesis. Scientific rationale in support of a micronutrient protocol to be used as an adjunct to standard or experimental cancer therapy is presented.

Historical perspective on the use of retinoids in cutaneous T-cell lymphoma (CTCL)

Vitamin A and its analogues influence differentiation and proliferation and may also alter immune responses. Limited clinical efficacy of these compounds given alone or as part of a combination therapy has been shown in various types of cutaneous T-cell lymphoma (CTCL), including mycosis fungoides, Sézary syndrome, and prelymphomatous disorders such as parapsoriasis en plaques. Compounds used mostly in small, nonrandomized trials are isotretinoin (13-cis-retinoic acid), etretinate, acitretin, and all-trans-retinoic acid. Clinical responses have been found despite persistent residual disease with atypical lymphocytes in various compartments. The exact mechanism of action of retinoids in CTCL is unclear and depends on the presence of retinoid receptors on the tumor cells, which is variable in different forms of CTCL. Therapies combining retinoids with psoralen-ultraviolet A or with interferons may have a synergistic effect, which deserves confirmation through randomized trials in the future.

Primary cutaneous T-cell lymphoma: review and current concepts

PURPOSE

Primary cutaneous T-cell lymphomas (CTCLs) encompass a wide variety of lymphomas that are characterized by the localization of the malignant lymphocytes to the skin at presentation. Advances in molecular biologic techniques, including immunophenotyping and gene rearrangement studies to determine clonality, have led to more frequent diagnosis of CTCL as well as more consistent subclassification of these entities. However, there continues to be confusion in the classification, prognosis, and management of patients with CTCL. The purpose of this review is to present a summary of the diagnosis, prognosis, and treatment of CTCL, with specific emphasis on mycosis fungoides (MF) and Sézary syndrome (SS). We also present a detailed discussion of the entities that make up the differential diagnosis of CTCL.

DESIGN

We reviewed the medical literature on CTCL and other diseases that make up the differential diagnosis of CTCL.

RESULTS AND CONCLUSION

MF and SS are the most common forms of CTCL. The etiology of this disease is still unknown. Patients may go for months to years with skin abnormalities before being diagnosed. MF/SS is an indolent disease and patients with T1 disease have a normal life expectancy. Patients who undergo transformation to large-cell lymphoma (8% to 23% of patients) have a poor prognosis, with mean survival ranging from 2 to 19 months. Treatment for MF/SS continues to be palliative. There are many new therapies that are currently being investigated in clinical trials, and the DAB(389)IL-2 fusion protein was recently approved for the treatment of refractory MF/SS.

Retinoids synergize with interleukin-2 to augment IFN-gamma and interleukin-12 production by human peripheral blood mononuclear cells

We have demonstrated previously that cells from both the skin and peripheral blood from patients with cutaneous T cell lymphoma (CTCL) have elevated levels of protein and mRNA for Th2 cytokines, interleukin-4 (IL-4) and IL-5, and depressed levels of Thl cytokines, IL-2 and interferon-gamma (IFN-gamma). Furthermore, IL-12 in vitro can restore IFN-gamma production by these patients' cells to near normal levels. Because retinoids exert therapeutic activity in CTCL and are potent modulators of growth and differentiation of hematopoietic cells, we investigated the role of retinoids in modulating Thl cytokine production. Peripheral blood mononuclear cells (PBMC) from normal donors and patients with CTCL were cultured with medium, IL-2, 13-cis-retinoic acid, all-trans-retinoic acid, acetretin or etretinate alone, or IL-2 plus the retinoids for 24 h, and levels of IFN-gamma were determined using ELISA. IL-2 or retinoids alone could induce low but significant levels of IFN-gamma. However, when IL-2 was cultured with each retinoid, a synergistic augmentation of IFN-gamma levels (4-fold to 90-fold) was observed except in the case of etretinate. All-trans-retinoic acid (ATRA) was the most potent IFN-y inducer. Similar studies performed using PBMC from CTCL patients indicated the IFN-gamma augmentation occurred but in a blunted manner. The IFN-y-inducing effect of ATRA and 13-cis-retinoic acid could be abrogated by addition of anti-IL-12 antibodies, suggesting that IL-12 plays a role in the synergistic upregulation of IFN-gamma. Using an IL-12 p40-specific radioimmunoassay (RIA), we confirmed the presence of IL-12 in IL-2 plus retinoid-treated culture supernatants. Purified monocytes cultured with IL-2 plus ATRA did not secrete IL-12. Only when monocytes were cocultured with lymphocytes was there an increase in IL-12 production, suggesting the involvement of a paracrine feedback loop requiring both monocytes and lymphocytes. These data suggest that retinoids can induce Th1 cytokines from normal and CTCL PBMC and that this induction may be mediated through IL-12 production.

High doses of multiple antioxidant vitamins: essential ingredients in improving the efficacy of standard cancer therapy

Numerous articles and several reviews have been published on the role of antioxidants, and diet and lifestyle modifications in cancer prevention. However, the potential role of these factors in the management of human cancer have been largely ignored. Extensive in vitro studies and limited in vivo studies have revealed that individual antioxidants such as vitamin A (retinoids), vitamin E (primarily alpha-tocopheryl succinate), vitamin C (primarily sodium ascorbate) and carotenoids (primarily polar carotenoids) induce cell differentiation and growth inhibition to various degrees in rodent and human cancer cells by complex mechanisms. The proposed mechanisms for these effects include inhibition of protein kinase C activity, prostaglandin E1-stimulated adenylate cyclase activity, expression of c-myc, H-ras, and a transcription factor (E2F), and induction of transforming growth factor-beta and p21 genes. Furthermore, antioxidant vitamins individually or in combination enhance the growth-inhibitory effects of x-irradiation, chemotherapeutic agents, hyperthermia, and biological response modifiers on tumor cells, primarily in vitro. These vitamins, individually, also reduce the toxicity of several standard tumor therapeutic agents on normal cells. Low fat and high fiber diets can further enhance the efficacy of standard cancer therapeutic agents; the proposed mechanisms for these effects include the production of increased levels of butyric acid and binding of potential mutagens in the gastrointestinal tract by high fiber and reduced levels of growth promoting agents such as prostaglandins, certain fatty acids and estrogen by low fat. We propose, therefore, a working hypothesis that multiple antioxidant vitamin supplements together with diet and lifestyle modifications may improve the efficacy of standard and experimental cancer therapies.

Incidence and in-vivo relevance of anti-interferon antibodies during treatment of low-grade cutaneous T-cell lymphomas with interferon alpha-2a combined with acitretin or PUVA

Interferon-alpha combined with retinoid or PUVA is used for the treatment of cutaneous T-cell lymphoma. Anti-IFN-alpha antibodies (IFN ab) occur regularly during IFN-alpha treatment. We investigated the incidence of neutralizing and binding IFN ab and analysed their relationship with clinical and immunological parameters. A group of 17 CTCL patients were treated with IFN alpha-2a three times weekly subcutaneously at a dose of 3 Mill. I.U. combined either with retinoid (acitretin, Neotigason; 0.5 mg/kg bodyweight) daily or with 5-methoxypsoralen (1.2 mg/kg bodyweight) plus UVA radiation three times weekly. Prior to and during treatment we monitored stage, skin involvement by a tumour burden index, serum levels of beta 2-microglobulin, neopterin, binding and neutralizing IFN ab, Interleukin-6 (IL-6), soluble IL-2 receptors (sIL-2r) and the CD4/CD8 ratio of peripheral blood mononuclear cells. We observed two complete, two partial and six minor responses, four patients with stable disease and three patients with progressive disease. Of the 17 patients, 7 developed binding IFN ab, but only 2 had neutralizing IFN ab which were associated with high titres of binding IFN ab. IFN ab formation was more frequent in patients with normal CD4/CD8 ratios and a high tumour burden index and showed a trend to be more frequent in PUVA-cotreated patients than in retinoid-cotreated patients. Responses were more frequently seen in IFN ab-negative patients. IFN ab developed in patients treated with PUVA or retinoid combined with IFN. Binding as well as neutralizing IFN ab may have an impact on the treatment success in CTCL patients.