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Biomedical subjects

L M Itri

Publications and source records attributed to L M Itri.

7 recordsLinked to original sources

The interferons.

In the 10 years since the interferons (IFN) entered large-scale clinical trials, much has been learned much about their uses as single agents. alpha-IFN, the most widely studied, has shown antitumor and antiviral efficacy against various tumors and tumor-related viruses; it has been approved by the Food and Drug Administration for the treatment of patients with hairy cell leukemia, acquired immune deficiency syndrome-related Kaposi sarcoma, and condylomata acuminata. Although IFN are effective as single agents in certain clinical situations, increasing experience with these cytokines suggests that their greatest therapeutic potential may be in combination with other biologic response-modifying, cytotoxic, or antiviral drugs. Trials combining alpha-IFN with 5-fluorouracil to treat colorectal carcinoma or with zidovudine to treat acquired immune deficiency syndrome have shown the significant impact that IFN administered in conjunction with other carefully selected agents can have. To design the most effective combination regimens, better preclinical models that clarify the mechanisms of action of IFN and define their biochemical interactions with other agents are needed.

Antineoplastic Combined Chemotherapy Protocols

13-cis-retinoic acid and interferon alpha-2a: effective combination therapy for advanced squamous cell carcinoma of the skin.

BACKGROUND: Retinoids (vitamin A derivatives) and interferon-alpha (IFN-alpha) are potent regulators of malignant cell differentiation and proliferation, and both have immunomodulatory and antiangiogenesis activity. A large body of preclinical and clinical data supports the use of combination therapy with 13-cis-retinoic acid (13-cRA) and IFN-alpha in patients with squamous cell carcinoma of the skin. This carcinoma is an extremely common and frequently severely disfiguring cancer, for which about 10% of patients remain uncured following standard local therapy. PURPOSE: Our purpose was to test whether a 20% or greater complete response rate could be achieved using a combination of these two agents in patients with advanced squamous cell carcinoma of the skin in whom local therapy had failed or was unfeasible or who had regional and/or distant metastases. METHODS: Thirty-two patients with heavily pretreated, advanced inoperable cutaneous squamous cell carcinoma of the skin were given a combination of oral 13-cRA (1 mg/kg per day) and subcutaneous recombinant human IFN alpha-2a (3 million units per day) for at least 2 months, unless disease progressed earlier, in a phase II trial. RESULTS: Nineteen (68%) of the 28 assessable patients responded, seven (25%) of whom had complete responses. Response rates were 93% (13 of 14) in patients with advanced local disease (six complete responses), 67% (four of six) in patients with regional disease (no complete responses), and 25% (two of eight) in patients with distant metastases (one complete response). The relationship between decreased response rate and increased extent of disease was highly statistically significant (P less than .005, chi-square test). The median response duration was greater than 5 months. No life-threatening toxic effects occurred in assessable patients treated with this combination, although dose reductions were required in 18 patients. The major limiting side effect in this elderly patient population (median age, 67 years) was cumulative fatigue. CONCLUSION: These results indicate that combined systemic therapy with 13-cRA and IFN alpha-2a is highly effective in patients with advanced squamous cell carcinoma of the skin.

Aged

Differentiation therapy of acute promyelocytic leukemia with tretinoin (all-trans-retinoic acid).

BACKGROUND AND METHODS: Patients with acute promyelocytic leukemia have a characteristic (15;17) translocation, with a breakpoint on chromosome 17 in the region of the retinoic acid receptor-alpha (RAR-alpha). Since this receptor has been shown to be involved with growth and differentiation of myeloid cells in vitro, and since recent clinical studies have reported that tretinoin (all-trans-retinoic acid) induces complete remission in patients with acute promyelocytic leukemia we studied the effects of tretinoin on cellular maturation and molecular abnormalities in patients undergoing the induction of remission with this agent. RESULTS: Eleven patients with acute promyelocytic leukemia were treated with tretinoin administered orally at a dose of 45 mg per square meter of body-surface area per day. Nine of the 11 patients entered complete remission. In two patients, complete remission was preceded by striking leukocytosis that then resolved despite continued drug treatment. Serial studies of cellular morphologic features, cell-surface immunophenotypic analysis, and fluorescence in situ hybridization with a chromosome 17 probe revealed that clinical response was associated with maturation of the leukemic clone. All patients who responded to treatment who were tested by Northern blot analysis had expression of aberrant RAR-alpha. As patients entered complete remission, the expression of the abnormal RAR-alpha message decreased markedly; however, it was still detectable in several patients after complete morphologic and cytogenetic remission had been achieved. CONCLUSIONS: Tretinoin is a safe and highly effective agent for inducing complete remission in patients with acute promyelocytic leukemia. Clinical response to this agent is associated with leukemic-cell differentiation and is linked to the expression of an aberrant RAR-alpha nuclear receptor. Molecular detection of the aberrant receptor may serve as a useful marker for residual leukemia in patients with this disease.

Administration, Oral

Loss of interferon antibodies during prolonged continuous interferon-alpha 2a therapy in hairy cell leukemia.

Although highly active in hairy cell leukemia (HCL), interferons (IFN) are not curative in this disease; current data indicate that prolonged IFN therapy will be necessary to control disease in the majority of patients. We previously observed acquired IFN resistance in association with neutralizing IFN-alpha 2a antibodies in small numbers of patients with HCL. This finding suggests that the requisite long-term therapy may be compromised if there is an increasing incidence over time of neutralizing antibodies. We performed a follow-up study of IFN antibodies in our patients receiving continuous IFN therapy. All 16 patients who were previously antibody negative remained so. Surprisingly, all nine patients who previously had non-neutralizing IFN antibodies became antibody negative after a median of 14.5 months. Moreover, 3 of 10 patients who had neutralizing antibodies became antibody negative and five had only non-neutralizing antibodies a median of 10 months from the time neutralizing antibody had first been detected. Only two patients had persisting neutralizing antibodies. Inhibition of neopterin synthesis, inhibition of generation of 2', 5' oligoadenylate synthetase activity, and inability to detect IFN in serum after subcutaneous injection of IFN-alpha 2a was observed only in the one patient tested with neutralizing IFN antibodies confirming that these antibodies have functional significance in vivo. We conclude that, although neutralizing IFN antibodies inhibit the effectiveness of IFN in vivo, these antibodies are produced only transiently during long-term therapy. The long-term effectiveness of this drug will not likely be affected in most patients by neutralizing antibody.

Antibodies

Interferon-alpha 2a in the treatment of acquired immunodeficiency syndrome-related Kaposi's sarcoma.

In a series of studies, recombinant interferon-alpha 2a (rIFN alpha 2a, Roferon-A) was administered alone (273 men) or combined with vinblastine (91 men) to patients with acquired immunodeficiency syndrome (AIDS)-related Kaposi's sarcoma (KS). Patients were treated with daily doses of rIFN alpha 2a ranging from 3 to 54 million international units (I.U.) administered intramuscularly. A dose of 36 million I.U. daily for approximately 10 weeks followed by a three times weekly maintenance schedule with the same dose resulted in the best overall therapeutic benefit. An escalating-dose regimen of 3, 9, and 18 million I.U. daily, each for 3 days, followed by 36 million I.U. daily, produced equivalent therapeutic benefit with amelioration of acute toxicity in some patients. Response was more likely in patients without a history of opportunistic infection or B symptoms (fever, night sweats, or weight loss). Response rate increased with increasing baseline CD4 lymphocyte count and was 45.5% in patients with a CD4 count of greater than 400/mm3. Responding patients with a CD4 count of greater than 200/mm3 had a distinct survival advantage over patients who had similar CD4 counts but whose tumors did not regress with therapy. The addition of vinblastine increased toxicity and did not improve the response rate or prolong survival. Side effects included fatigue, fever, chills, myalgias, headaches, anorexia, nausea, diarrhea, and dizziness. Mild abnormalities in hematologic and liver function tests occurred in some patients. Most adverse effects diminished or resolved with continued therapy. We conclude that rIFN alpha 2a offers important therapeutic benefit in a select group of patients with AIDS-related KS.

Acquired Immunodeficiency Syndrome

Prevention of second primary tumors with isotretinoin in squamous-cell carcinoma of the head and neck.

BACKGROUND: Patients with head-and-neck cancers who are free of disease after local therapy remain at high risk for both recurrent and second primary tumors. Retinoids have proved efficacious in the treatment of premalignant oral lesions and are promising agents for the prevention of epithelial carcinogenesis. METHODS: We prospectively studied 103 patients who were disease-free after primary treatment for squamous-cell cancers of the larynx, pharynx, or oral cavity. After completion of surgery or radiotherapy (or both), these patients were randomly assigned to receive either isotretinoin (13-cis-retinoic acid) (50 to 100 mg per square meter of body-surface area per day) or placebo, to be taken daily for 12 months. RESULTS: There were no significant differences between the two groups in the number of local, regional, or distant recurrences of the primary cancers. However, the isotretinoin group had significantly fewer second primary tumors. After a median follow-up of 32 months, only 2 patients (4 percent) in the isotretinoin group had second primary tumors, as compared with 12 (24 percent) in the placebo group (P = 0.005). Multiple second primary tumors occurred in four patients, all of whom were in the placebo group. Of the 14 second cancers, 13 (93 percent) occurred in the head and neck, esophagus, or lung. CONCLUSIONS: Daily treatment with high doses of isotretinoin is effective in preventing second primary tumors in patients who have been treated for squamous-cell carcinoma of the head and neck, although it does not prevent recurrences of the original tumor.

Adult