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Phase I Study in Cancer Patients of a Replication-Defective Avipox Recombinant Vaccine That Expresses Human Carcinoembryonic Antigen

From the Georgetown University Medical Center, Vincent T. Lombardi Cancer Center, Washington, DC; and Laboratory of Tumor Immunology and Biology, Division of Basic Science, National Cancer Institute, National Institutes of Health, Bethesda, MD.

Address reprint requests to John L. Marshall, MD, Lombardi Cancer Center, 3800 Reservoir Rd, NW, Washington, DC 20007.

	ABSTRACT

TOP ABSTRACT INTRODUCTION PATIENTS AND METHODS RESULTS DISCUSSION REFERENCES

 
PURPOSE: A phase I clinical trial in patients with advanced carcinoma was conducted, using a replication-defective avipox vaccine containing the gene for the human carcinoembryonic antigen (CEA). The canarypox vector, designated ALVAC, has the ability to infect human cells but cannot replicate.

PATIENTS AND METHODS: The recombinant vaccine, designated ALVAC-CEA, was administered intramuscularly three times at 28-day intervals. Each cohort of six patients received three doses of either 2.5 x 10⁵, 2.5 x 10⁶, or 2.5 x 10⁷ plaque-forming units of vaccine.

RESULTS: The vaccine was well tolerated at all dose levels and no significant toxicity was attributed to the treatment. No objective antitumor response was observed during the trial in patients with measurable disease. Studies were conducted to assess whether ALVAC-CEA had the ability to induce cytolytic T-lymphocyte (CTL) responses in patients with advanced cancer. Peripheral blood mononuclear cells (PBMCs) from patients with the MHC class I A2 allele were obtained before vaccine administration and 1 month after the third vaccination. Peripheral blood mononuclear cells were incubated with the CEA immunodominant CTL epitope carcinoembryonic antigen peptide-1 and interleukin 2 and quantitated using CTL precursor frequency analysis. In seven of nine patients evaluated, statistically significant increases in CTL precursors specific for CEA were observed in PBMCs after vaccination, compared with before vaccination.

CONCLUSION: These studies constitute the first phase I trial of an avipox recombinant in cancer patients. The recombinant vaccine ALVAC-CEA seems to be safe and has been demonstrated to elicit CEA-specific CTL responses. These studies thus form the basis for the further clinical exploration of the ALVAC-CEA recombinant vaccine in phase I/ II studies in protocols designed to enhance the generation of human T-cell responses to CEA.

	INTRODUCTION

TOP ABSTRACT INTRODUCTION PATIENTS AND METHODS RESULTS DISCUSSION REFERENCES

 
CARCINOEMBRYONIC ANTIGEN (CEA) is a glycoprotein of 180,000 molecular weight found in normal fetal colon. In the human adult, CEA and other members of its family have been found in normal colonic mucosa, saliva, feces, serum, and colonic lavages.¹ However, CEA is overexpressed in virtually all adenocarcinomas of the colon and rectum and is present on most adenocarcinomas of the breast, lung, pancreas, and other regions of the gastrointestinal tract.^2-4 In many colorectal carcinomas and in carcinomas at other sites, CEA is produced in high quantities and is measurable in the serum.⁵ Because of this, CEA has become one of the most widely used serologic markers of malignancy, particularly in patients with colorectal cancer.

Carcinoembryonic antigen is a member of the immunoglobulin superfamily and is theorized to be an intercellular recognition and adhesion molecule.⁶ These molecules are thought to determine the specificity of cell to cell or cell to substrate interactions and therefore may have a role in invasion and metastasis. However, CEA expression or upregulation has not been found to predict tumor behavior reliably or to correlate with cellular differentiation.^7,8 Carcinoembryonic antigen and other related molecules (eg, nonspecific cross-reacting antigen) have been mapped to the short and the long arms of chromosome 19.⁹ Although CEA is overexpressed in most adenocarcinomas, it is a normal antigen that is expressed during fetal development as well as in low levels in the gut crypts and healing intestinal mucosa. Therefore, it is not surprising that there is little if any immune response to it when it is overexpressed on cells and/or when it is shed into the serum. Although the sera of some patients have been reported to contain CEA-immunoglobulin complexes, circulating levels of CEA in the thousands of nanograms per milliliter are tolerated in cancer patients without immune complex deposition syndromes or other evidence of immune-mediated activity.¹⁰

Carcinoembryonic antigen as an immunologic target has been the focus of many researchers.^11-16 A recombinant vaccinia (rV) virus has been developed that contains in its genome and expresses in infected cells the CEA gene and gene product. In a preclinical model, the rV-CEA vaccine has been demonstrated to protect immunologically intact mice against the challenge of the CEA-transduced tumor cells and to reduce or eliminate the growth of established tumors.¹⁷ The safety of this agent in nonhuman primates has also been established.¹⁸ In a phase I clinical trial,¹¹ the safety of this vaccine construct was demonstrated in cancer patients but no significant antineoplastic effect was shown. Possible reasons for the lack of clinical efficacy in this trial were the prior exposure to the vaccinia virus in all patients treated, which led to the development of antivaccinia immune responses on repeated dosings of the vaccine; the advanced state of tumors in patients; and potentially decreased immune status of patients due to prior chemotherapy regimens.

The phase I clinical trial using rV-CEA did demonstrate, for the first time, that CEA-specific cytolytic T-lymphocyte (CTL) responses could be elicited in humans through administration of a vaccine.^11,19 As a consequence of the studies, a CEA immunodominant CTL epitope has been identified. This 9-mer amino acid (YLSGANLNL) was shown to bind to HLA-A2 class I and has been designated carcinoembryonic antigen peptide-1 (CAP-1). Several subsequent studies have also demonstrated the ability of CAP-1 to elicit CEA-specific human CTL responses.^16,19,20 Moreover, stable CTL lines derived by culture of peripheral blood mononuclear cells (PBMCs) from rV-CEA–vaccinated patients with CAP-1 and interleukin (IL)-2 have recently been described.¹⁹

ALVAC, a member of the avianpox virus family, offers a potential alternative to the use of vaccinia as a vector or may be used in combination with vaccinia recombinants in diversified prime-and-boost immunization protocols.²¹ In contrast to vaccinia virus, which infects mammalian cells, replicates, and can then go on to infect other cells, ALVAC undergoes abortive replication in mammalian cells. It infects cells, expresses its transgene product(s) for 14 to 21 days, and then is unable to infect other cells.²² Therefore, systemic infections would not be possible as with vaccinia. Second, humans are unlikely to have had prior exposure to this virus. In a similar preclinical model, the protective and antitumor activity of the ALVAC-CEA vaccine has been demonstrated in immunologically competent mice.²¹ The safety of this vector has been documented in human trials against infectious diseases and in severely immunocompromised mice.^23,24 The evidence given here thus justifies a clinical study of ALVAC-CEA in humans with incurable CEA-positive tumors.

	PATIENTS AND METHODS

TOP ABSTRACT INTRODUCTION PATIENTS AND METHODS RESULTS DISCUSSION REFERENCES

 
Patient Eligibility
To be eligible for this phase I trial, patients had to meet the following criteria: advanced, incurable malignancy (patients with stage IV malignancy but without radiographic evidence of disease were eligible); serum CEA level at least 10 ng/mL at some point in the past or tumor that stained positively for CEA by immunohistochemical techniques; age at least 18 years; anticipated survival of 6 months; ability to give informed consent; performance status (Eastern Cooperative Oncology Group) 0 or 1; WBC count at least 3,000/µL, absolute neutrophil count at least 1,500/µL, and platelet count at least 100,000/µL; prothrombin time and partial thromboplastin time within normal ranges; normal serum creatinine level or creatinine clearance at least 60 mL/min; adequate immunologic function, defined by normal delayed-type hypersensitivity, normal CD4:CD8 ratio (> 1), or normal immunoelectrophoresis; human immunodeficiency virus seronegativity; no other diagnoses of altered immune function; no prior radiation to more than 50% of all nodal groups; and no concurrent use of steroids. Contraindications to enrollment included history of another malignancy in the past 2 years, prior radiation to the pelvis, recent major surgery, pregnancy or lactation, serious intercurrent illness, and clinically evident brain metastasis.

Treatment
Treatment consisted of three injections of ALVAC-CEA given 4 weeks apart. Three dose levels were planned: 2.5 x 10⁵, 2.5 x 10⁶, and 2.5 x 10⁷ plaque-forming units (pfu). Six patients were to be treated at each of the three dose levels. Three of the six in each cohort were HLA-A2 positive for immunologic monitoring purposes. If no toxicity was seen after the completion of treatment in five of the six patients at a given dose level, six new patients were enrolled at the next higher dose level. The vaccine was administered intramuscularly in two equally divided doses (for volume purposes), using the Biojector 2000 (Bioject Inc., Portland, OR) needle-free system, into the arm, thighs, or buttocks (the injection site was rotated). Patients were monitored before each injection and 4 weeks after the final injection by physical examination, measurement of performance status, performance of complete blood counts, determination of prothrombin time and partial thromboplastin time, determination of chemistry profile, urinalysis, and measurement of CEA level and PBMCs. Tumor responses were evaluated after completion of all vaccinations. Patients not completing the three vaccinations for any reason were replaced to ensure an adequate evaluation of the toxicity at a given dose level.

Vaccine Preparation
ALVAC-CEA is a recombinant canarypox virus that contains the entire human CEA gene, inserted into its genome. The vaccine was manufactured by Pasteur-Mérieux Serums et Vaccins (Marcy, France)/Virogenetics (Troy, NY). The canarypox strain from which ALVAC was derived was first isolated at the Rentschler Bakteriologisches Institute, Lauphein, Württemberg, Germany, where it was attenuated by serial passage in chick embryo fibroblasts. The recombinant virus was grown and generated on chick embryo fibroblasts from pathogen-free flocks qualified for vaccine production. The vaccine was vialed at 2.5 x 10⁷ pfu/0.2 mL. Vaccine vials were kept at -70°C until the day of administration. They were then thawed at room temperature or in a 37°C bath. The sample in the vial was diluted with sterile saline to a total volume of 500 µL at each dose level and then divided into two 250-µL syringes for the Bioject system. Dilutions were performed in a sterile hood.

Immunologic Monitoring Methods: Precursor Frequency Analyses
Carcinoembryonic antigen peptide-1 (CEA amino acid position 571–579; YLSGANLNL) was generated on a peptide synthesizer (model 432A, Applied Biosystem, Foster City, CA), and the product was dissolved in aqueous solution, sterile filtered, and frozen at -70°C at a concentration of 2 mg/mL. The purity of the peptides was more than 90%, as analyzed by high-performance liquid chromatography.

Limiting dilution assays²⁵ were used to determine the CTL precursor frequency to CAP-1 in the prevaccination and postvaccination PBMCs from HLA-A2–positive patients. Various numbers of PBMCs were seeded into 96-well flat-bottom plates (Corning Costar, Cambridge, MA), with 10⁴ autologous PBMCs irradiated with 4,000 rads and incubated with 50 µg/µL of CAP-1. At least 48 cultures were set up for each dilution of PBMCs. Cultures were incubated for 5 days with CAP-1 at 37°C in a humidified atmosphere containing 5% CO₂. The cultures were then supplemented with recombinant IL-2 (10 Cetus units/mL) for 11 days, with IL-2 medium replenished every 3 days. The 5 days of incubation with peptide plus the 11 days with IL-2 constituted one in vitro stimulation cycle. After two in vitro stimulation cycles, the CTL activity was tested for each well against C1R-A2 target cells with and without incubation with CAP-1, using the procedure described earlier, with one exception: unlabeled K562 cells were added to each assay at a ratio of 10 unlabeled K562 cells to one target cell, to eliminate the natural killer cell activity. Precursor frequencies were calculated by ² minimization, as described previously.²⁶ Individual counts obtained from each experimental well were compared with the mean counts from the controls on the same plate. Limiting dilution assays of PBMCs were conducted to quantitate CEA-specific CTL precursors before and after immunization with ALVAC-CEA. Cytolytic T-cell activity that was greater than the mean plus three SDs of the control wells was considered significant.

	RESULTS

TOP ABSTRACT INTRODUCTION PATIENTS AND METHODS RESULTS DISCUSSION REFERENCES

 
Twenty patients were accrued for this trial. Patient characteristics are listed in Table 1. Seven patients received ALVAC-CEA at doses of 2.5 x 10⁵ pfu (dose level 1), seven at doses of 2.5 x 10⁶ pfu (dose level 2), and six at doses of 2.5 x 10⁷ pfu (dose level 3). One additional patient was accrued at dose levels 1 and 2, because two patients had to be taken out of the study after only a single vaccination for rapidly progressing disease. Patient no. 20 completed only two of the three injections secondary to disease progression and was not replaced, because sufficient toxicity data had been obtained from the other five patients treated in this cohort. All other patients received all three vaccine injections. Approximately 40 patients were screened for this trial but were ineligible, primarily because of being HLA-A2 negative.

Toxicity
ALVAC-CEA was well tolerated at all dose levels. No significant toxicity could be attributed to treatment. Skin reactions were mild, if they occurred at all. Mild injection-site soreness was occasionally reported. Patient no. 2 developed hemorrhagic diarrhea after the first injection of ALVAC-CEA but was found to have ischemic bowel disease secondary to adhesions and torsion. Pathologic review of the bowel segment removed failed to show any abnormal immunologic infiltrate. No other diarrhea or gastrointestinal toxicity was noted during the trial.

Clinical Response
No objective antitumor response was observed during the trial in the 15 patients who had assessable or measurable disease. Because many of the patients had only subradiographic or microscopic disease at the time of treatment, we focused on the time to progression in the patients treated. These data are summarized in Table 2. Patient no. 16 presented with poorly differentiated adenocarcinoma of unknown primary tumor, metastatic to soft tissue over his left scapula. He underwent radiation therapy to this lesion but his CEA level decreased only to 12.8 ng/mL. After his first vaccine treatment, he was diagnosed with brain metastasis and underwent radiation therapy, which resulted in resolution of all neurologic symptoms. He then received the two remaining injections of ALVAC-CEA. His CEA level normalized and he remained without disease progression for 15 months, after which his CEA level began to increase again. He is currently being treated with vaccinia-CEA and more ALVAC-CEA under a separate protocol. Patient no. 6 was diagnosed with locally advanced pancreatic cancer, underwent radiation therapy with chemosensitization, and then was treated with ALVAC-CEA after clinical and radiographic progression of her disease. She remained stable for 6 months, after which the disease progressed. She then received further chemotherapy but failed to respond. Patient no. 11 presented with an obstructing gastric adenocarcinoma with diffuse peritoneal seeding. He was treated with both systemic and intraperitoneal chemotherapy and remained without radiographic evidence of disease after this therapy. He then received three injections of ALVAC-CEA. After 5 months, he was noted to have recurrent disease, again obstructing his gastric outlet, and he underwent surgical resection. Autologous tumor and other tumor cell lines were tested with use of the patient's own T-cell line, obtained after the vaccine treatment. Results of these assays are summarized in Table 3. The patient's T cells were able to lyse his own tumor under these conditions as well as lyse allogeneic cell lines that expressed CAP-1 and CEA. Approximately 1 year later, the patient was revaccinated with vaccinia-CEA under a separate protocol. Three days after the injection, he developed marked diffuse lymphadenopathy. Biopsy specimens showed only adenocarcinoma consistent with his gastric primary tumor. No histologic evidence for an immune response was found. Three other patients (patient nos. 10, 12, and 17) had evidence of tumor stabilization, with 5, 5, and 9 months of progression-free survival after vaccination.

Immunologic Responses
The 9-mer amino acid CTL epitope for CEA, designated CAP-1, has recently been identified. This CAP-1 was designed for, and demonstrated to conform to, an HLA-A2 allele–binding motif. The HLA-A2 allele, which is expressed in approximately 50% of the population, was thus assayed for all patients in this trial. Nine patients, three in each cohort, were HLA-A2 positive. Peripheral blood mononuclear cells from each of these HLA-A2–positive patients were obtained both before and after three administrations of ALVAC-CEA and were assayed for CTL responses to CEA.

A statistically significant increase in CTL precursors (as measured by the Student's paired t test) after ALVAC-CEA immunization, compared with before immunization, was seen for PBMCs from two of three patients who were immunized at dose level 1. For example, the CTL precursor frequency of PBMCs obtained from patient no. 6 (who had pancreatic cancer) was one in 37,434 after immunization, compared with one in 126,110 before immunization. All three patients who received the vaccine at dose level 2, and two of three patients who were vaccinated at dose level 3, had statistically significant increases in CTL precursors after vaccination, compared with before vaccination. Two patients (patient no. 5, vaccinated at dose level 1; and patient no. 18, vaccinated at dose level 3) showed slight increases in precursor frequencies after immunization, but these increases were not statistically significant (P > .2) (Table 4).

	DISCUSSION

TOP ABSTRACT INTRODUCTION PATIENTS AND METHODS RESULTS DISCUSSION REFERENCES

 
This phase I study demonstrated the safety of ALVAC-CEA administration to patients with advanced carcinomas. The study also demonstrated the ability of ALVAC-CEA to induce CEA-specific CTL responses in patients with advanced, CEA-expressing carcinoma. No objective evidence for an anticancer response was seen, apart from the normalization of the CEA level in patient no. 16. Although seven of nine HLA-A2–positive patients showed increases in CEA-specific CTL precursors, there was no obvious dose response (ie, patients receiving the higher dose of ALVAC recombinant did not seem to have higher levels of CTL precursors). The reason remains unclear at this time, but the following possible explanations exist: (a) 2.5 x 10⁵ pfu (dose level 1) of ALVAC-CEA is sufficient to induce CTL responses and higher doses are superfluous; (b) there were not enough patients in each cohort (only three patients per group); (c) vaccine was administered to a heterogeneous population, which included patients with colorectal carcinoma, carcinoma of the pancreas, cervix, or stomach, or unknown primary tumor; and (d) some patients with advanced cancer may be unable to respond to such therapy because of pre-existing immune suppression. The last possibility is supported by the finding of low absolute CD4 and CD8 counts in patients no. 5 and no. 18, who also failed to show improvement in precursor frequencies (Table 2). These factors, as well as others, may have influenced the immune response in our patients.

In the studies reported here, our intent was to assay for CTL responses. To do this, we used a 9-mer peptide that has previously been shown to bind to MHC class I (A2 allele).¹¹ The CAP-1 epitope seems unrelated to determinants recognized by B cells. Carcinoembryonic antigen peptide-1 is at amino acid position 571–579 at CEA, toward the 3' end, not at the N-terminal domain; it is in the B3 domain. Soluble CEA was not used because it processes through the MHC class II pathway and would monitor efficiently not for CTL responses but for lymphoproliferative responses. Other parts of the CEA molecule also contain CTL determinants. We and others have previously shown that HLA-A3 and HLA-A24 determinants also exist. In the future, mixtures of these peptides for different determinants could be used. Moreover, CAP-1 is not the only HLA-A2 determinant on CEA. We have shown that there are six others, but CAP-1 is the strongest binder to HLA-A2 and produced the best results in terms of CTL responses.¹¹

Use of the ALVAC-CEA vaccine is not limited to the 50% of the population that is positive for HLA-A2. As discussed earlier in this article, other alleles are present, which in combination with HLA-A2 account for almost 90% of the population. A limitation of our study is that monitoring, using CAP-1, was done only for HLA-A2–positive patients. This peptide was used to clearly define a proof of the concept that CTL responses to CEA could be induced with ALVAC-CEA. The fact that we were unable to monitor the degree of response in patients negative for HLA-A2 does not mean there was no clinical response in these patients. Efforts to expand the number of monitoring tools are ongoing.

Carcinoembryonic antigen is an oncofetal antigen that is expressed during fetal development as well as in normal colonic mucosa. Thus, induction of an immune response to such a "self-antigen" was previously thought improbable. The studies reported here that used ALVAC-CEA recombinant add more evidence for the potential immunogenicity of CEA and more support for the use of CEA as a target for immunotherapy. A previous clinical study involving a vaccinia-CEA recombinant¹¹ and an ongoing clinical trial using CAP-1–pulsed dendritic cells (Deng et al, manuscript in preparation) have demonstrated the induction of CEA-specific CTL responses. Moreover, other immunogens—such as an anti-idiotype monoclonal antibody to an anti-CEA monoclonal antibody¹² and recombinant CEA protein^13,14—have shown induction of both CEA-specific antibody and proliferative T-cell responses. In vitro studies have also recently shown induction of human CTL responses to CEA.^16,19,20

The level of precursors induced in this phase I study of ALVAC-CEA was relatively low. This could have been due to at least one of several factors. Because this was a phase I study, the low precursor frequency observed could have been caused by (a) the lowered immune status of the patients, which has been demonstrated both through a decrease in the chain of the T-cell receptor and through a shift from a T-cell type 1 to a T-cell type 2 response; (b) the size of or possibly high interstitial pressures of tumor masses; and/or (c) the presence of putative immune inhibitors such as transforming growth factor beta or IL-10. Moreover, CTL precursors were quantitated from PBMCs, whereas greater quantities could be found in lymph nodes. In this study, only three doses of vaccine were administered, at monthly intervals. Perhaps more immunizations, or longer intervals between immunizations, would be more efficient.

Previous preclinical studies have shown that the combination of ALVAC-CEA as a boost, with rV-CEA as a primary immunization, was better at inducing T-cell responses than was the use of ALVAC-CEA or rV-CEA alone.²² Preclinical studies with rV-CEA also showed that local administration of granulocyte-macrophage colony-stimulating factor at the immunization site, or systemic administration of low-dose IL-2 after rV-CEA vaccination, also enhanced CEA-specific T-cell responses²⁷ (Greiner et al, manuscript in preparation). Recently, we initiated a clinical trial to determine the validity of heterologous immunization (ie, rV-CEA followed by ALVAC-CEA immunization) as well as of the use of granulocyte-macrophage colony-stimulating factor and IL-2 as biologic adjuvants for recombinant vaccines. Furthermore, studies have recently been initiated on the use of a recombinant ALVAC dual-transgene vector expressing the genes for both CEA and the human T-cell costimulatory molecule B7.1. We have reported the first use of an ALVAC recombinant in an anticancer vaccine setting, and we believe our findings validate the use of this recombinant to induce immune responses in cancer patients more efficiently.

	ACKNOWLEDGMENTS

 
Supported by grant nos. U01 CA62500 and 2 P30 CA51008 from the National Cancer Institute

	REFERENCES

TOP ABSTRACT INTRODUCTION PATIENTS AND METHODS RESULTS DISCUSSION REFERENCES

 
1. Rogers GT: Carcinoembryonic antigens and related glycoproteins: Molecular aspects and specificity. Biochim Biophys Acta 695:227-249, 1983[Medline]

2. Muraro R, Wunderlich D, Thor A, et al: Definition by monoclonal antibodies of a repertoire of epitopes on carcinoembryonic antigen differentially expressed in human colon carcinomas versus normal human adult tissues. Cancer Res 45:5769-5780, 1985[Abstract/Free Full Text]

3. Steward AM, Nixon D, Zamcheck N, et al: Carcinoembryonic antigen in breast cancer patients: Serum levels and disease progress. Cancer 33:1246-1252, 1974[Medline]

4. Vincent RG, Chu TM: Carcinoembryonic antigen in patients with carcinoma of the lung. J Thorac Cardiovasc Surg 66:320-328, 1978[Medline]

5. Ladenson JH, McDonald JM, Landt M, et al: Colorectal carcinoma and carcinoembryonic antigen (CEA). Clin Chem 26:1213-1220, 1980[Free Full Text]

6. Benchimol S, Fuks A, Jothy S, et al: Carcinoembryonic antigen, a human tumor marker, functions as an intercellular adhesion molecule. Cell 57:327-334, 1989[Medline]

7. Midiri G, Amanti C, Benedetti M, et al: CEA tissue staining in colorectal cancer patients. Cancer 55:2624-2629, 1985[Medline]

8. Kodera Y, Isobe K, Yamauchi M, et al: Expression of carcinoembryonic antigen (CEA) and nonspecific crossreacting antigen (NCA) in gastrointestinal cancer: The correlation with degree of differentiation. Br J Cancer 68:130-136, 1993[Medline]

9. Zimmerman W, Weber B, Ortlieb B, et al: Chromosomal localization of the carcinoembryonic antigen gene family and differential expression in various tumors. Cancer Res 48:2550-2554, 1988[Abstract/Free Full Text]

10. Fuchs C, Krapf F, Kern P, et al: CEA-containing immune complexes in sera of patients with colorectal cancer and breast cancer: Analysis of complexed immunoglobulin classes. Cancer Immunol Immunother 26:180-184, 1988[Medline]

11. Tsang KY, Zaremba S, Nieroda CA, et al: Generation of human cytotoxic T cells specific for human carcinoembryonic antigen epitopes from patients immunized with recombinant vaccinia-CEA vaccine. J Natl Cancer Inst 87:982-990, 1995[Abstract/Free Full Text]

12. Foon KA, Chakraborty M, John WJ, et al: Immune response to the carcinoembryonic antigen in patients treated with an anti-idiotype antibody vaccine. J Clin Invest 96:334-342, 1995

13. Fagerberg J, Samanci A, Yi Q, et al: Recombinant carcinoembryonic antigen and granulocyte-macrophage-colony stimulating factor for active immunization of colorectal carcinoma patients. J Immunother 19:461, 1996 (abstr)

14. Conry RM, Saleh MN, Schlom J, et al: Human immune response to carcinoembryonic antigen tumor vaccines. J Immunother 18:137, 1995 (abstr)

15. Philip R, Brunette E, Alters S, et al: Gene modified and peptide pulsed dendritic cells for the generation of active immunotherapy strategies. J Immunother 19:467, 1996 (abstr)

16. Alters SE, Gadea JR, Sorich M, et al: Dendritic cells pulsed with CEA peptide induce CEA specific CTL with restricted TCR repertoire. J Immunother 21:17-26, 1998

17. Kantor J, Irvine K, Abrams S, et al: Anti-tumor activity and immune responses induced by a recombinant vaccinia-carcinoembryonic antigen (CEA) vaccine. J Natl Cancer Inst 84:1084-1091, 1992[Abstract/Free Full Text]

18. Kantor J, Irvine K, Abrams S, et al: Immunogenicity and safety of a recombinant vaccinia virus expressing the carcinoembryonic antigen (CEA)-vaccine in a non-human primate. Cancer Res 52:6917-6925, 1992[Abstract/Free Full Text]

19. Tsang KY, Zhu MZ, Nieroda CA, et al: Phenotypic stability of a cytotoxic T-cell line directed against an immunodominant epitope of human carcinoembryonic antigen. Clin Cancer Res 3:2439-2449, 1997[Abstract/Free Full Text]

20. Zaremba S, Barzaga E, Zhu MZ, et al: Identification of an enhancer agonist CTL peptide from human carcinoembryonic antigen. Cancer Res 57:4570-4577, 1997[Abstract/Free Full Text]

21. Hodge JW, McLaughlin JP, Kantor JA, et al: Diversified prime and boost protocols using recombinant vaccinia virus and recombinant nonreplicating avian pox virus to enhance T-cell immunity and antitumor responses. Vaccine 16:759-768, 1997

22. Taylor J, Paoletti E: Fowlpox virus as a vector in non-avian species. Vaccine 6:466-468, 1988[Medline]

23. Fries LF, Tartaglia J, Taylor J, et al: Human safety and immunogenicity of a canarypox-rabies glycoprotein recombinant vaccine: An alternative poxvirus vector system. Vaccine 14:428-434, 1996[Medline]

24. Tartaglia J, Weinberg R, Languet B, et al: A highly attenuated strain of vaccinia virus. Vaccine 9:190-193, 1991[Medline]

25. Coulie PG, Somville M, Lehmann F, et al: Precursor frequency analysis of human cytotoxic T lymphocytes directed against autologous melanoma cells. Int J Cancer 50:289-297, 1992[Medline]

26. Taswell C: Limiting dilution assays for determination of immunocompetent cell frequencies: I. Data analysis. J Immunol 126:1614-1619, 1981[Abstract]

27. McLaughlin JP, Schlom J, Kantor JA, et al: Improved immunotherapy of a recombinant CEA vaccinia vaccine when given in combination with interleukin-2. Cancer Res 56:2361-2367, 1996[Abstract/Free Full Text]

Submitted April 21, 1998; accepted August 27, 1998.

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				M. A. Morse, T. M. Clay, A. C. Hobeika, T. Osada, S. Khan, S. Chui, D. Niedzwiecki, D. Panicali, J. Schlom, and H. K. Lyerly Phase I Study of Immunization with Dendritic Cells Modified with Fowlpox Encoding Carcinoembryonic Antigen and Costimulatory Molecules Clin. Cancer Res., April 15, 2005; 11(8): 3017 - 3024. [Abstract] [Full Text] [PDF]

				A. J. Redwood, M. Messerle, N. L. Harvey, C. M. Hardy, U. H. Koszinowski, M. A. Lawson, and G. R. Shellam Use of a Murine Cytomegalovirus K181-Derived Bacterial Artificial Chromosome as a Vaccine Vector for Immunocontraception J. Virol., March 1, 2005; 79(5): 2998 - 3008. [Abstract] [Full Text] [PDF]

				K. Y. Tsang, C. Palena, J. Yokokawa, P. M. Arlen, J. L. Gulley, G. P. Mazzara, L. Gritz, A. Gomez Yafal, S. Ogueta, P. Greenhalgh, et al. Analyses of Recombinant Vaccinia and Fowlpox Vaccine Vectors Expressing Transgenes for Two Human Tumor Antigens and Three Human Costimulatory Molecules Clin. Cancer Res., February 15, 2005; 11(4): 1597 - 1607. [Abstract] [Full Text] [PDF]

				J. L. Marshall, J. L. Gulley, P. M. Arlen, P. K. Beetham, K.-Y. Tsang, R. Slack, J. W. Hodge, S. Doren, D. W. Grosenbach, J. Hwang, et al. Phase I Study of Sequential Vaccinations With Fowlpox-CEA(6D)-TRICOM Alone and Sequentially With Vaccinia-CEA(6D)-TRICOM, With and Without Granulocyte-Macrophage Colony-Stimulating Factor, in Patients With Carcinoembryonic Antigen-Expressing Carcinomas J. Clin. Oncol., February 1, 2005; 23(4): 720 - 731. [Abstract] [Full Text] [PDF]

				H. L. Kaufman Integrating Bench With Bedside: The Role of Vaccine Therapy in the Treatment of Solid Tumors J. Clin. Oncol., February 1, 2005; 23(4): 659 - 661. [Full Text] [PDF]

				H. E. Zeytin, A. C. Patel, C. J. Rogers, D. Canter, S. D. Hursting, J. Schlom, and J. W. Greiner Combination of a Poxvirus-Based Vaccine with a Cyclooxygenase-2 Inhibitor (Celecoxib) Elicits Antitumor Immunity and Long-Term Survival in CEA.Tg/MIN Mice Cancer Res., May 15, 2004; 64(10): 3668 - 3678. [Abstract] [Full Text] [PDF]

				J. W. Hodge, D. J. Poole, W. M. Aarts, A. Gomez Yafal, L. Gritz, and J. Schlom Modified Vaccinia Virus Ankara Recombinants Are as Potent as Vaccinia Recombinants in Diversified Prime and Boost Vaccine Regimens to Elicit Therapeutic Antitumor Responses Cancer Res., November 15, 2003; 63(22): 7942 - 7949. [Abstract] [Full Text] [PDF]

				G. J. Ullenhag, J.-E. Frodin, S. Mosolits, S. Kiaii, M. Hassan, M. C. Bonnet, P. Moingeon, H. Mellstedt, and H. Rabbani Immunization of Colorectal Carcinoma Patients with a Recombinant Canarypox Virus Expressing the Tumor Antigen Ep-CAM/KSA (ALVAC-KSA) and Granulocyte Macrophage Colony- stimulating Factor Induced a Tumor-specific Cellular Immune Response Clin. Cancer Res., July 1, 2003; 9(7): 2447 - 2456. [Abstract] [Full Text] [PDF]

				J. W. Hodge, D. W. Grosenbach, W. M. Aarts, D. J. Poole, and J. Schlom Vaccine Therapy of Established Tumors in the Absence of Autoimmunity Clin. Cancer Res., May 1, 2003; 9(5): 1837 - 1849. [Abstract] [Full Text] [PDF]

				I. D. Davis, M. Jefford, P. Parente, and J. Cebon Rational approaches to human cancer immunotherapy J. Leukoc. Biol., January 1, 2003; 73(1): 3 - 29. [Abstract] [Full Text] [PDF]

				D. H Palmer, M.-J. Chen, and D. J Kerr Gene therapy for colorectal cancer Br. Med. Bull., December 1, 2002; 64(1): 201 - 225. [Abstract] [Full Text] [PDF]

				J. W. Greiner, H. Zeytin, M. R. Anver, and J. Schlom Vaccine-based Therapy Directed against Carcinoembryonic Antigen Demonstrates Antitumor Activity on Spontaneous Intestinal Tumors in the Absence of Autoimmunity Cancer Res., December 1, 2002; 62(23): 6944 - 6951. [Abstract] [Full Text] [PDF]

				H. Kobayashi, R. Omiya, M. Ruiz, E. Huarte, P. Sarobe, J. J. Lasarte, M. Herraiz, B. Sangro, J. Prieto, F. Borras-Cuesta, et al. Identification of an Antigenic Epitope for Helper T Lymphocytes from Carcinoembryonic Antigen Clin. Cancer Res., October 1, 2002; 8(10): 3219 - 3225. [Abstract] [Full Text] [PDF]

				E. S. Kass, J. W. Greiner, J. A. Kantor, K. Y. Tsang, F. Guadagni, Z. Chen, B. Clark, R. D. Pascalis, J. Schlom, and C. Van Waes Carcinoembryonic Antigen as a Target for Specific Antitumor Immunotherapy of Head and Neck Cancer Cancer Res., September 1, 2002; 62(17): 5049 - 5057. [Abstract] [Full Text] [PDF]

				S. Dermime, A. Armstrong, R. E Hawkins, and P. L Stern Cancer vaccines and immunotherapy Br. Med. Bull., July 1, 2002; 62(1): 149 - 162. [Abstract] [Full Text] [PDF]

				S. H. van der Burg, A. G Menon, A. Redeker, M.-C. Bonnet, J. W. Drijfhout, R. A. E. M. Tollenaar, C. J. H. van de Velde, P. Moingeon, P. J. K. Kuppen, R. Offringa, et al. Induction of p53-specific Immune Responses in Colorectal Cancer Patients Receiving a Recombinant ALVAC-p53 Candidate Vaccine Clin. Cancer Res., May 1, 2002; 8(5): 1019 - 1027. [Abstract] [Full Text] [PDF]

				N. L. Berinstein Carcinoembryonic Antigen as a Target for Therapeutic Anticancer Vaccines: A Review J. Clin. Oncol., April 15, 2002; 20(8): 2197 - 2207. [Abstract] [Full Text] [PDF]

				A C Armstrong and R E Hawkins Vaccines in oncology: background and clinical potential Br. J. Radiol., November 1, 2001; 74(887): 991 - 1002. [Abstract] [Full Text] [PDF]

				K. Y. Tsang, M. Zhu, J. Even, J. Gulley, P. Arlen, and J. Schlom The Infection of Human Dendritic Cells with Recombinant Avipox Vectors Expressing a Costimulatory Molecule Transgene (CD80) to Enhance the Activation of Antigen-specific Cytolytic T Cells Cancer Res., October 1, 2001; 61(20): 7568 - 7576. [Abstract] [Full Text] [PDF]

				I. Motta, F. Andre, A. Lim, J. Tartaglia, W. I. Cox, L. Zitvogel, E. Angevin, and P. Kourilsky Cross-Presentation by Dendritic Cells of Tumor Antigen Expressed in Apoptotic Recombinant Canarypox Virus-Infected Dendritic Cells J. Immunol., August 1, 2001; 167(3): 1795 - 1802. [Abstract] [Full Text] [PDF]

				D. W. Grosenbach, J. C. Barrientos, J. Schlom, and J. W. Hodge Synergy of Vaccine Strategies to Amplify Antigen-specific Immune Responses and Antitumor Effects Cancer Res., June 1, 2001; 61(11): 4497 - 4505. [Abstract] [Full Text] [PDF]

				M. von Mehren, P. Arlen, J. Gulley, A. Rogatko, H. S. Cooper, N. J. Meropol, R. K. Alpaugh, M. Davey, S. McLaughlin, M. T. Beard, et al. The Influence of Granulocyte Macrophage Colony-Stimulating Factor and Prior Chemotherapy on the Immunological Response to a Vaccine (ALVAC-CEA B7.1) in Patients with Metastatic Carcinoma Clin. Cancer Res., May 1, 2001; 7(5): 1181 - 1191. [Abstract] [Full Text]

				E. Kass, D. L. Panicali, G. Mazzara, J. Schlom, and J. W. Greiner Granulocyte/Macrophage-Colony Stimulating Factor Produced by Recombinant Avian Poxviruses Enriches the Regional Lymph Nodes with Antigen-presenting Cells and Acts as an Immunoadjuvant Cancer Res., January 1, 2001; 61(1): 206 - 214. [Abstract] [Full Text]

				J. L. Marshall, R. J. Hoyer, M. A. Toomey, K. Faraguna, P. Chang, E. Richmond, J. E. Pedicano, E. Gehan, R. A. Peck, P. Arlen, et al. Phase I Study in Advanced Cancer Patients of a Diversified Prime-and-Boost Vaccination Protocol Using Recombinant Vaccinia Virus and Recombinant Nonreplicating Avipox Virus to Elicit Anti-Carcinoembryonic Antigen Immune Responses J. Clin. Oncol., December 1, 2000; 18(23): 3964 - 3973. [Abstract] [Full Text] [PDF]

				R. Ignatius, M. Marovich, E. Mehlhop, L. Villamide, K. Mahnke, W. I. Cox, F. Isdell, S. S. Frankel, J. R. Mascola, R. M. Steinman, et al. Canarypox Virus-Induced Maturation of Dendritic Cells Is Mediated by Apoptotic Cell Death and Tumor Necrosis Factor Alpha Secretion J. Virol., December 1, 2000; 74(23): 11329 - 11338. [Abstract] [Full Text]

				M. von Mehren, P. Arlen, K. Y. Tsang, A. Rogatko, N. Meropol, H. S. Cooper, M. Davey, S. McLaughlin, J. Schlom, and L. M. Weiner Pilot Study of a Dual Gene Recombinant Avipox Vaccine Containing Both Carcinoembryonic Antigen (CEA) and B7.1 Transgenes in Patients with Recurrent CEA-expressing Adenocarcinomas Clin. Cancer Res., June 1, 2000; 6(6): 2219 - 2228. [Abstract] [Full Text]

				M. Zhu, J. Marshall, D. Cole, J. Schlom, and K. Y. Tsang Specific Cytolytic T-Cell Responses to Human CEA from Patients Immunized with Recombinant Avipox-CEA Vaccine Clin. Cancer Res., January 1, 2000; 6(1): 24 - 33. [Abstract] [Full Text]

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