Recombinant alpha-2 interferon therapy for Kaposi's sarcoma associated with the acquired immunodeficiency syndrome

Combination chemotherapy of disseminated Kaposi's sarcoma in patients with the acquired immune deficiency syndrome

Two clinical trials were conducted to assess the efficacy and safety of a combination chemotherapy regimen for the treatment of Kaposi's sarcoma in patients with the acquired immune deficiency syndrome (AIDS). Eighteen consecutive patients with disseminated Kaposi's sarcoma were treated with a six-drug regimen of doxorubicin (Adriamycin), vinblastine, bleomycin/actinomycin D, vincristine, dacarbazine (ABV/ADV). A brief partial or complete response was achieved in 13 patients. Most patients died of opportunistic infections. Eighteen consecutive patients with disseminated Kaposi's sarcoma were then randomly assigned to therapy with either recombinant alpha interferon or ABV/ADV. The treatment responses in these two groups were comparable to results of earlier trials, and the incidence of opportunistic infections during therapy did not differ between the two treatment arms. It is concluded that chemotherapy is effective and safe for use in palliative management of Kaposi's sarcoma in patients with AIDS.

Treatment of Kaposi's sarcoma with interferon alfa-2b (Intron A)

The activity of the alpha interferons against AIDS-related Kaposi's sarcoma (KS) has been demonstrated in numerous clinical trials. Unfortunately, most reports have involved small patient cohorts and a variety of dosages and schedules of administration. We report here a series of Phase II trials with interferon alfa-2b (Intron A, Schering Corp., Kenilworth, NJ) involving 114 patients using three dose regimens. Patients received 50 X 10(6) IU/m2 intravenously (high dose), 30 X 10(6) IU/m2 subcutaneously (intermediate dose), or 1 X 10(6) IU/m2 subcutaneously (low dose). Clinical responses were seen in all regimens and, overall, 35% of the patients obtained complete or partial remissions. The response rates in the low-, intermediate-, and high-dose groups were 33%, 28%, and 45%, respectively. In addition, high-dose therapy was associated with more rapid time to response. Patients with low-stage (I or II) disease and those who lack B symptoms were more likely to respond to therapy; i.e., response rates for patients without B symptoms were 38%, 44%, and 60% in the low-, intermediate-, and high-dose groups, respectively. Seventy (61%) patients had died at the time of data collection, with a median survival of 15 months. Disease stage and the presence of B symptoms significantly affected mortality. Responders enjoyed significantly longer survival (P less than 0.10) than did nonresponders both overall and when adjusted for disease stage. Interferon alfa-2b was generally well tolerated, although almost all patients experienced flu-like symptoms. No life-threatening toxicities occurred and only six (6%) patients discontinued treatment due to adverse reactions. No significant improvement in immunologic parameters was detected during this study. These studies suggest that, in this disease setting, interferon alfa-2b may be acting through direct antiproliferative effects rather than as an immunomodulator, and higher doses appear to be more effective than very low doses.

Acquired immunodeficiency syndrome of childhood

AIDS of childhood is reviewed in this timely article, including care of the child with infectious complications, and other current and future management concerns.

Biology and therapy of epidemic Kaposi's sarcoma

Kaposi's sarcoma, once a rarely seen neoplasm in the West, now occurs in an epidemic fashion in association with acquired immune deficiency syndrome (AIDS). The pathogenesis of Kaposi's sarcoma is still unclear but it appears to be an endothelial neoplasm. Its clinical presentation may be quite subtle and varied. The natural history of Kaposi's sarcoma is still not fully defined, and its rate of progression may be either relatively indolent or aggressive. Therapies include local radiation, recombinant interferon alfa-2a, and cytotoxic chemotherapy. For a subset of patients with Kaposi's sarcoma who were treated with recombinant interferon alfa-2a, the disease is in complete remission, without opportunistic infection, and they appear to be culture-negative for the etiologic retrovirus that causes their immune deficiency. Interferon alfa-2a appears to have antineoplastic efficacy, (and may have antiretroviral efficacy as well) in this epidemic neoplasm.

Management of infectious and immunological complications of acquired immunodeficiency syndrome (AIDS). Current and future prospects

AIDS is caused by a newly recognised virus (human immunodeficiency virus; HIV) which induces a profound defect in cellular immune function associated with increased susceptibility to opportunistic infections and certain malignancies. The clinical presentation of HIV ranges from asymptomatic infection to severe immunodeficiency manifesting as severe life-threatening infectious diseases or malignancies. While major research efforts are being directed toward development of vaccine and discovery of effective antiretroviral drugs, clinicians are faced with AIDS patients with multiple and complicated medical problems including opportunistic infections and certain malignancies. Currently, efforts are directed toward early diagnosis, treatment, and prevention of recurrence of these opportunistic infections. The current approaches are reviewed in this article. Major recent developments in AIDS research include the isolation of the HIV on culture and the availability of the antibody test. Aside from vaccine and antiretroviral drugs, other measures that may be of benefit in the treatment of AIDS patients are immunological enhancement and reconstitution. Several studies are underway to evaluate antiviral agents in the treatment of HIV infection. Those undergoing clinical trial include suramin, ribavirin, antimoniotungstate, phosphonoformate and azidothymidine. Immune enhancers that have been used include alpha- and gamma-interferon and interleukin-2. HLA-matched lymphocyte transfusions and bone marrow transplantations have been used alone and in combination to replace the AIDS patient's defective immune system.

Toxicities of human recombinant interferon-alpha 2 in patients with advanced prostate carcinoma

Nine patients with hormone-resistant prostate carcinoma were treated with subcutaneous injection of recombinant human interferon-alpha 2 (rHuIFN-alpha 2), 5-10 X 10(6) U/m2, three times a week. One patient had a mixed clinical response with reduction of bone pain. The study was closed due to intolerable grade III and IV toxicities including weight loss (8/9), fatigue/malaise (7/9), central nervous system toxicity (4/9), leukopenia (3/9), and uncontrollable nausea and vomiting (2/9). These toxicities resulted in deterioration of performance status. It is concluded that rHuIFN-alpha 2, at least at the dose and schedule studied, should not be used for the treatment of patients with hormone-resistant prostate carcinoma.

Antiproliferative effects of interferons on human melanoma cells in the human tumor colony-forming assay

The human tumor colony-forming assay (HTCFA) is an in vitro test that has been used to predict the activity of anticancer drugs against a patient's tumor. We utilized the assay to analyze the antiproliferative effects of seven interferons (IFNs) against 40 human melanomas to determine which IFN had the greatest antiproliferative activity in this drug-resistant tumor. IFNs studied included recombinant IFN-alpha 2; human lymphoblastoid IFN; IFN-alpha Cantell; native beta RPMI; two recombinant IFNs-beta; and recombinant IFN-gamma. Growth was sufficient [greater than 30 tumor colony-forming units (TCFU)/well] for assessing the antiproliferative effects of at least one IFN in 25 tumors (63%). A dose-response relationship was demonstrated by all IFNs in tumors in which some activity was observed (p less than or equal to 0.01). Individual melanomas differed in their sensitivities to the various IFNs. Overall, however, none of the IFNs was markedly more effective in antiproliferative effects than any other, although there was a trend toward IFN-beta ser having more potent antiproliferative properties when compared to IFN-alpha 2 (p = 0.055). Twelve of 13 tumors exposed to combinations of IFN-beta ser and IFN-gamma demonstrated a synergistic antiproliferative effect. In all but two of these, low concentrations of each IFN (less than or equal to 50 U/ml), when combined, resulted in 85-95% inhibition. As prolonged exposure to high concentrations of IFN are often not clinically tolerable, these data suggest that IFN combinations may be one way of achieving more clinically meaningful IFN doses, schedules, and regimens, provided antiproliferative effects are of importance in vivo.

Direct and cell-mediated effects of interferon-alpha and -gamma on cells chronically infected with HTLV-III

The replication of the human T lymphotropic retrovirus HTLV-III in persistently infected cells is relatively insensitive to the direct antiviral action of human interferon-alpha or -gamma (IFN-alpha or -gamma), showing only a two- to threefold reduction of HTLV-III, even though the host cells are very sensitive to IFN, as shown by vesicular stomatitis virus (VSV)-yield reduction assay (4-5 log reduction of VSV). However, IFN anticellular activity is strongly enhanced in the presence of normal peripheral blood mononuclear cells, suggesting a cell-mediated effect of IFNs.

Recombinant human interferon gamma suppresses HTLV-III replication in vitro

Effect of human interferon gamma (rINF gamma) on HTLV-III replication was evaluated quantitatively via a novel infection system using HTLV-I-carrying MT-4 cells. Treatment of HTLV-III-infected MT-4 cells with different concentrations (I-1,000 U/ml) of rINF gamma, which did not affect the growth or viability of uninfected cells, significantly blocked the appearance of immunofluorescent antigens of HTLV-III and the virus-induced cytopathic effect in a dose-dependent manner. A plaque assay was applied to measure the exact amount of viral particles released from HTLV-III-infected MT-4 cultures either untreated or treated with rINF gamma after infection. The number of plaques per dish decreased with increasing drug concentrations. About 50% and 80% of HTLV-III replication were inhibited by the addition of 100 and 1,000 U/ml of rINF gamma, respectively. The effects of INF were observed by day 5 of incubation with the chemical. However, longer treatment of cells with rINF gamma permitted a gradual increase in viral replication. Re-addition of fresh INF into cultures did not change this pattern significantly.

The antitumor effects of interferon

Interferons show antitumor activity in patients with various malignancies. The mechanism(s) of the antitumor effects are not altogether clear. In one experimental animal model discussed herein, mice were injected with Friend erythroleukemia cells and treated with mouse interferon alpha/beta. The results suggest that interferon does not act directly on the tumor cells but acts via host mechanisms that are still ill defined.

Kaposi's sarcoma of the penis in a patient with the acquired immune deficiency syndrome

We report a case of secondary Kaposi's sarcoma of the penis and the acquired immune deficiency syndrome. Recognition of the penile lesion as being secondary Kaposi's sarcoma is paramount, since the clinical course appears to be dependent upon systemic disease. Local therapy is reserved for palliation upon disease recurrence.

Kaposi's sarcoma and the acquired immunodeficiency syndrome

This review has briefly summarized the place of KS in the AIDS epidemic, offering a framework for more critical evaluation of difficult therapeutic decisions. It should be expected (and it is hoped) that with the current rapid pace of AIDS research, many of these issues will be resolved shortly, and that therapy will become more rational. Until then, however, conventional approaches will be used. Given the hazards of these, it is incumbent upon the physician to remain up to date on developments in this rapidly evolving field.

Treatment of the acquired immune deficiency syndrome

The acquired immune deficiency syndrome (AIDS) and AIDS-related complex (ARC) are sequelae of immune system injury initiated by a novel human retrovirus [human T-lymphotrophic virus strain III/lymphadenopathy-associated virus (HTLV III/LAV)]. The resulting spectrum of immune deficiency sets the stage for opportunistic infection and malignancy. In this review, we consider progress made in the treatment and prevention of AIDS and HTLV III/LAV infection. Immunomodulator and antiviral approaches are discussed.

Heterogeneity of epidemic Kaposi's sarcoma. Implications for therapy

Kaposi's sarcoma (KS) in acquired immune deficiency syndrome (AIDS) is a new manifestation of a previously rare disease, and generally has a fatal course. Variations in the clinical course and in response to treatment by patients with this disease suggest that specific immunologic or clinical parameters may be important in the prognosis. Retrospective analyses of clinical parameters with respect to survival in 96 patients with epidemic Kaposi's sarcoma indicated that earlier tumor stage, the lack of prior opportunistic infections, and the absence of systemic symptoms correlated most closely with survival. Sixteen immune parameters were also assessed for their prognostic value. Total T4 (CD-4) cell number levels and the T4: T8 ratio correlated most closely with survival. Response to treatment with recombinant alpha interferons, while not well correlated with tumor stage, was more frequent in patients without systemic symptoms or a history or prior opportunistic infections. Treatment response was associated with a greater degree of intact T-cell function. These findings emphasize the importance of cellular immunity in the pathogenesis and subsequent course of patients with epidemic Kaposi's sarcoma, suggesting that different therapeutic strategies may be necessary to address specific prognostic subgroups.

Induction of T-cell proliferation and enhancement of NK activity by supernatants from Con A-stimulated human peripheral blood mononuclear cells: a new lymphokine

Supernatants from human peripheral blood mononuclear cells activated by Con A contain a factor(s) that stimulates blastogenic activity of normal human peripheral blood mononuclear cells. This Con A supernatant (CAS) contains stimulatory activity for E-rosette positive lymphocytes (T cells) and requires adherent cells for stimulation of T-cell proliferation. CAS does not contain detectable amounts of IL-2 as determined by its inability to support CTLL cell growth. Nor does it contain IL-1 or interferon. Examination of functional activity of lymphocytes stimulated for 3 days by CAS revealed that NK activity is augmented. This supernate does not appear to have any direct effect on B-cell function, although it induces suppression of polyclonal PWM stimulation of immunoglobulins. Thus, CAS appears to contain a new cytokine with immunomodulating potential.

The effects of long-term administration of recombinant alpha-2 interferon on lymphocyte subsets, proliferation, and suppressor cell function in multiple sclerosis

The immunological effects of long-term treatment with recombinant alpha-2 interferon (rIFN-alpha 2) were investigated in multiple sclerosis (MS) patients treated with 2 X 10(6) units of IFN or a placebo three times per week for one year. A mild lymphopenia was observed in IFN patients who also showed a decrease in the absolute number of total T cells in the blood (OKT3 binding cells); however, the percentage of cells reacting with OKT3, OKT4, and OKT8 antibodies did not change significantly during the study. The percentage of cells reacting with the Leu-7 antibody, which recognizes NK cells, was unchanged. During MS exacerbations, placebo patients showed a tendency for decreased levels of OKT3 and OKT8 cells. In contrast, IFN patients did not demonstrate a decrease in either OKT3 or OKT8 cells during disease attacks. Concanavalin A (ConA)-induced suppressor cell activity was depressed in both IFN and placebo-treated patients during attacks. Lymphoproliferative responses to phytohemagglutinin, pokeweed mitogen, and ConA were unchanged. These studies demonstrate that long-term treatment with rIFN-alpha 2 induces a generalized T-cell lymphopenia, but at this dose does not significantly affect the profiles of T-cell subsets and suppressor cell function in MS patients.

Biological therapy of cancer

Interferons and monoclonal antibodies are among the most promising biological approaches to cancer treatment which have so far been investigated. Both natural and recombinant interferon-alpha preparations have shown activity in a number of trials in hematologic malignancies, even in previously treated patients; activity in solid tumors, however, has been limited. Unconjugated monoclonal antibodies have been safely administered in several small trials and have had therapeutic value on occasion. In spite of a number of remaining problems and questions, monoclonal antibodies and their conjugates seem likely to find a number of distinct roles in cancer treatment; elimination of micrometastases and purging of bone marrow for grafting may be among these roles.

Antibody levels for cytomegalovirus, herpes simplex virus, and rubella in patients with acquired immune deficiency syndrome

Significantly higher proportions of patients with acquired immune deficiency syndrome (AIDS) or lymphadenopathy syndrome (LAS) were positive for antibodies to cytomegalovirus (CMV) and herpes simplex virus (HSV) compared with control groups of commercial blood donors. In contrast, no differences were found in the incidence of individuals positive for antibodies to rubella in these groups of subjects. Of those positive for antibodies to CMV and HSV in each group, the mean antibody levels were significantly higher in AIDS-LAS patients compared with the controls. The entire distribution of antibody concentrations to CMV and HSV in AIDS patients was shifted upward, so that significantly more patients showed high values and significantly fewer showed low values, indicating hyperactive humoral immune responses to these viruses. In sharp contrast, the AIDS patients with antibody levels for rubella showed the same distribution of antibody levels as did two groups of controls. No correlation was found between concentrations of CMV and HSV antibodies in individual AIDS-LAS patients.

Acquired immunodeficiency syndrome

The acquired immunodeficiency syndrome (AIDS) was recognized as a distinct clinical entity in 1981 and was characterized by unexplained opportunistic infections and an aggressive form of Kaposi's sarcoma. High risk groups for contracting AIDS include homosexual men, parenteral drug users, hemophiliacs, recipients of blood and blood products, and heterosexual contacts of such individuals. Immunologic abnormalities associated with AIDS include lymphopenia, functional T-cell deficits, B-lymphocyte defects, and various serologic abnormalities. The causative virus has been identified as the human T-lymphotropic virus/lymphadenopathy associated virus (HTLV-III/LAV). AIDS represents the severe end of the clinical spectrum of infection with HTLV-III/LAV. Other manifestations are asymptomatic carriage, generalized lymphadenopathy, and a set of non-specific symptoms, termed the AIDS-related-complex (ARC). Although seen predominantly in the United States, AIDS has a world-wide occurrence. No known therapy for AIDS exists. Research efforts are being directed at antiviral therapy, immunorestoration and the development of a vaccine.

The use of plasmapheresis, lymphocytapheresis, and staph protein-A immunoadsorption as an immunomodulatory therapy in patients with AIDS and AIDS-related conditions

Circulating immune complexes, autoantibodies, and suppressor factors to normal lymphoproliferation may play an important role in the induction and maintenance of the cellular immunodeficiency characteristic for the acquired immunodeficiency syndrome (AIDS) and its related conditions. In order to explore the possibility that the removal of circulating humoral factors may have an immunomodulatory effect in patients with AIDS and AIDS-related conditions (ARC), we used apheresis procedures to treat patients with different clinical presentations of AIDS and ARC. Five patients with AIDS and opportunistic infections were treated with plasmapheresis. Four patients with AIDS and Kaposi's sarcoma without opportunistic infections were treated with staph protein-A immunoadsorption and two patients with ARC and peripheral neuropathy were treated with lymphoplasmapheresis. The treatments were tolerated well by all patients. Effective removal of circulating humoral immune factors was observed in all three groups. No significant clinical benefit was seen in the patients with AIDS and opportunistic infections treated with plasmapheresis. Partial tumor responses were observed in three of the four patients with AIDS related Kaposi's sarcoma treated with staph protein-A plasma perfusion, and resolution of neurologic symptoms was seen in both patients with ARC and peripheral neuropathy treated with lymphoplasmapheresis. Our preliminary results suggest that lymphoplasmapheresis may be an effective treatment modality for patients with ARC related peripheral neuropathy, that protein-A immunoadsorption is well tolerated by patients with AIDS-related Kaposi's sarcoma, and that this treatment has antitumor and immunomodulatory effects in these patients.

Kaposi's sarcoma and AIDS

Mucocutaneous lesions are often a prominent manifestation of the acquired immune deficiency syndrome (AIDS). Patients with this syndrome are susceptible to a number of opportunistic skin infections as well as an aggressive form of Kaposi's sarcoma. The diagnosis, the clinical setting, and the treatment of these diseases are discussed.

Effect of azimexon therapy on host defense parameters and disease-associated symptoms in the acquired immune deficiency syndrome (AIDS) and AIDS-related complex (ARC)

Azimexon, a 2-cyan-aziridinyl immune modulator, was given at a dose of 250 mg/m2/day for 10 days IV to 12 patients with AIDS and 16 with AIDS related complex (ARC). A decrease in total number of AIDS related symptoms from 43 to 24 and in mean number from 2.6 to 1.5 was observed among ARC patients (p less than .01). The most commonly improved symptoms were diarrhea, fatigue, and weight loss with the least frequently improved being lymphadenopathy. The following improvements in immune parameters were observed among ARC patients. DTH to recall antigens improved with an increase in number of positive tests from 35 to 47 and in mean number of positive skin tests from 2.2 on day 0 to 2.9 on day 14 (P less than .05). The geometric mean of the absolute lymphocyte count was 1.395 X 10(3)/microliter on day 0 with a significant increase of 18.0 percent on day 5 (P less than .01) and a 7.7 percent increase on day 21. The geometric mean of the OKT4+ cells on day 0 was 0.250 X 10(3)/microliter with a 33.3 percent increase on day 5 (P less than .07) and a 14.1 percent increase on day 21. T4/T8 ratio increased by 32.7 percent on day 5 (P less than .05) and by 19.4 percent on day 21 from an initial geometric mean of 0.339 X 10(3)/microliter on day 0. The geometric mean of GVH responses increased by 18.2 percent on day 5 (P less than .05) and by 24.0 percent on day 21 (P less than .07) from an initial value of 41.04 mm3. No symptomatic or immunologic improvements were observed among AIDS patients, but rather a significant decrease in mitogenic responses. PHA responses decreased by 70.3 percent on day 5 (P less than .05) and 42.2 percent on day 21 from an initial geometric mean of 4.02 X 10(3) cpm/10(3). Con-A responses decreased by 75.1 percent on day 5 (P less than .05) and increased by 20.3 percent on day 21 from an initial value of 1.14 X 10(3)/10(5) cells. Pretreatment number of absolute OKT4+ cells was the most significant prognostic survival variable. Thus, 8/9 patients with less than 0.10 X 10(3) OKT4+ blood cell/microliter subsequently died as compared to only 1/17 with greater than or equal to 0.10 X 10(3) OKT4+ cells (p less than .001). The only toxic effect of this treatment was mild hemolysis which disappeared upon cessation of treatment.(ABSTRACT TRUNCATED AT 400 WORDS)

The new alpha interferons

Alpha interferons are biological response modifiers that regulate immune function, slow cell proliferation, and inhibit virus replication. Large supplies of purified preparations are now available for clinical trials. Common toxicity includes an influenza-like syndrome to which tolerance occurs after several doses, and chronic fatigue and anorexia that may be dose-limiting. Myelosuppression is mild. Alpha interferons have established clinical activity against several human cancers, including melanoma, Kaposi's sarcoma, multiple myeloma, non-Hodgkin's lymphoma, hairy cell leukemia, and renal cell carcinoma. These data and alpha interferon nomenclature are summarized in table form. Intranasal alpha interferon is effective in prophylaxis of common viral upper respiratory tract infections, although toxicity in long-term use is prohibitive. Short-term administration to high risk populations may be most useful. Optimal doses and schedules need to be determined for all indications.

Human lymphoblastoid interferon treatment of Kaposi's sarcoma in the acquired immune deficiency syndrome. Clinical response and prognostic parameters

Thirty consecutive patients with the acquired immune deficiency syndrome were treated with intramuscular human lymphoblastoid interferon for Kaposi's sarcoma. Patients were divided into three groups receiving 7.5 million units/m2 per day, 15 million units/m2 per day, or 25 million units/m2 per day for 28 days. Because of dose-limiting toxicity in the highest dose group, all patients received between 6 and 15 million units/m2 per day. There were three partial responses and four minor responses. The responses were not dependent on drug dose, but did correlate with higher total lymphocyte and OKT4-positive lymphocyte numbers and absence of prior opportunistic infection. Patients who had endogenous acid-labile alpha-interferon prior to therapy were more likely to have progressive disease during interferon administration.

Neurological manifestations of the acquired immunodeficiency syndrome (AIDS): experience at UCSF and review of the literature

In this review of the acquired immunodeficiency syndrome (AIDS), the authors have evaluated a total of 352 homosexual patients with AIDS or generalized lymphadenopathy managed at the University of California, San Francisco (UCSF), between 1979 and 1984. Of an initial unselected group of 318 patients, 124 (39%) were neurologically symptomatic, and one-third already had their neurological complaints at the time of presentation. An additional 210 AIDS patients with neurological symptoms have been reported in the literature. Thus, a total of 366 neurologically symptomatic patients with AIDS or lymphadenopathy are reviewed. Central nervous system (CNS) complications, encountered in 315 patients, included the following viral syndromes: subacute encephalitis (54), atypical aseptic meningitis (21), herpes simplex encephalitis (nine), progressive multifocal leukoencephalopathy (six), viral myelitis (three), and varicella-zoster encephalitis (one). Non-viral infections were caused by Toxoplasma gondii (103), Cryptococcus neoformans (41), Candida albicans (six), Mycobacteria (six), Treponema pallidum (two), coccidioidomycosis (one), Mycobacterium tuberculosis (one), Aspergillus fumigatus (one), and Escherichia coli (one). Neoplasms included primary CNS lymphoma (15), systemic lymphoma with CNS involvement (12), and metastatic Kaposi's sarcoma (three). Cerebrovascular complications were seen in four patients with hemorrhage and five with infarction. Five patients in the UCSF series had multiple intracranial pathologies, including two cases of simultaneous Toxoplasma gondii infections and primary CNS lymphoma, two cases of coexistent Toxoplasma gondii and viral infections, and one case of combined Toxoplasma gondii and atypical mycobacterial infection. Cranial or peripheral nerve complications, seen in 51 patients, included cranial nerve syndromes secondary to chronic inflammatory polyneuropathy (five), lymphoma (five), and Bell's palsy (five). Peripheral nerve syndromes included chronic inflammatory polyneuropathy (12), distal symmetrical neuropathy (13), herpes zoster radiculitis (six), persistent myalgias (two), myopathy (two), and polymyositis (one). In light of the protean behavior of AIDS and the problems related to the clinical, radiological, and serological diagnosis of the unusual and varied associated nervous system diseases, patients with AIDS and neurological complaints require a rigorous and detailed evaluation. The authors' experience suggests that biopsy of all CNS space-occupying lesions should be performed for tissue diagnosis prior to the institution of other therapies.

AIDS and the gut

The epidemiological, immunological and early virological observations on the acquired immune deficiency syndrome (AIDS) suggested that an agent was involved which was sexually, parenterally and perinatally transmitted and perhaps tropic for T helper lymphocytes. A new subgroup of human T lymphotropic retroviruses have been identified ans seroepidemiological studies suggest that they are aetiologically related to AIDS. The syndrome is characterised by the development of tumors: such as Kaposi's sarcoma and non-Hodgkins lymphoma, with an aggressive clinical course and infection by a wide spectrum of opportunistic organisms. Both the tumours and the infections commonly involve the gut.

A phase I trial of recombinant gamma interferon in patients with cancer

A total of 11 patients were treated on an escalating, single dose trial of recombinant gamma interferon (rIFN-gamma), 6 patients by the i.m. and 5 patients by the i.v. route of administration. Dose ranges within each individual were from 0.05 mg/m2 of IFN (1 mg greater than or equal to 10 X 10(6) units of IFN) escalating to 10 mg/m2. All dosages were delivered twice weekly and the i.v. dose was infused over 5 min. The most common toxicities encountered included fever, chills, fatigue, anorexia, and granulocytopenia. The influenza-like symptoms were very similar to those encountered with IFN-alpha but were generally less severe. The granulocytopenia was dose-related and transient with recovery generally seen within 48-72 h following administration of rIFN-gamma. Absolute granulocyte counts only rarely dropped below 1000 mm3. Hepatotoxicity was not observed. IFN levels were determined by both a bioassay and an enzyme-linked immunosorbent assay. By the i.v. route, the peak level of IFN activity could usually be seen at completion of the infusion with a serum half-life of 30 min. By the i.m. route, the peak level of serum activity was generally detected between 4-8 h with a serum half-life of 4.5 h after the initial elimination phase. Peak IFN levels appeared to correlate with maximum toxicity. One patient with melanoma had a 25% reduction in a cutaneous lesion, but there were no other minimal, partial, or complete responses.

Acquired immunodeficiency syndrome (AIDS)--apheresis and operative risks

The removal of immune complexes, autoantibodies and suppressor factors from the circulation of patients with AIDS and AIDS related conditions by plasmapheresis and selective immunoadsorption may play a role as a therapeutic modality in these disorders. Lymphocytapheresis may also be of potential use in AIDS related conditions with presumed autoimmune basis. Perfusion of plasma over immobilized protein A columns is being evaluated as a possible immunomodulatory and antitumor therapy in patients with AIDS related Kaposi's sarcoma. Although apheresis procedures as a therapeutic modality in AIDS related conditions are still at the experimental stage, preliminary results are encouraging. The possible transmission of the disease by blood products presents a health hazard to health workers involved in the field of apheresis. Since the mode of transmission of the disease appears to be similar to hepatitis B, strict hepatitis B precautions should be enforced in every case in which AIDS suspected blood is being processed.

Treatment of advanced non-Hodgkin's lymphoma with recombinant leukocyte A interferon

We report the results of a trial of recombinant leukocyte A interferon in previously treated patients with non-Hodgkin's lymphoma who were no longer responsive to chemotherapy. Patients received recombinant leukocyte A interferon (50 X 10(6) U per square meter of body-surface area) by intramuscular injection three times weekly for three months or longer. Forty-five patients were enrolled in the study, and 37 were evaluated for a response. Thirteen of 24 (54 per cent) evaluable patients with low-histologic-grade non-Hodgkin's lymphoma had objective responses (nine partial responses and four histologically confirmed complete responses). Two of six (33 per cent) with intermediate-grade lymphoma responded (one partially and one completely), and one of seven (14 per cent) with high-grade lymphoma had a partial response. The median duration of responses was eight months. Four of the five complete responders have continued to receive maintenance interferon and have been in complete remission for 3, 7, 9, and 12 months, respectively; one had a recurrence at a site of previous disease seven months after interferon had been stopped. Side effects were noted in most patients. All 16 responders had been heavily pretreated with combination chemotherapy, including doxorubicin in 8 of the 16. These results suggest that recombinant leukocyte A interferon may be an effective new therapy for some patients with low- and intermediate-grade non-Hodgkin's lymphoma.