SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM 8-K

                                 CURRENT REPORT
                       PURSUANT TO SECTION 13 OR 15(d) OF
                       THE SECURITIES EXCHANGE ACT OF 1934

                Date of Report (Date of earliest event reported):

                                  May 20, 2002

                               Aphton Corporation
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             (Exact name of registrant as specified in its charter)



Delaware                            0-19122                        95-3640931
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(State or Other             (Commission File Number)            (I.R.S. Employer
Jurisdiction of                                                  Identification
Incorporation)                                                      Number)


             80 S.W. Eighth Street, Suite 2160, Miami, Florida 33130
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               (Address of principal executive offices) (zip code)

                                 (305) 374-7338
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              (Registrant's telephone number, including area code)


          -------------------------------------------------------------
          (Former name or former address, if changed since last report)

<PAGE>

ITEM 5.  OTHER EVENTS.

     On Monday, May 20, 2002, Aphton Corporation (the "Company")  announced that
the interim results from several  clinical trials and studies with the Company's
anti-gastrin  17 immunogen  (G17DT) were  presented at the annual meeting of the
American Society of Oncology (ASCO) held in Orlando, Florida.

     On Monday,  May 20, 2002,  investigators from the University of Nottingham,
UK, and the Derbshire Royal Infirmary, UK, presented the results from a Phase II
study with patients with histologically  proven Stage IV gastric cancer who were
treated with Aphton's G17DT,  but with no chemotherapy  administered.  Of the 10
evaluable patients,  the median survival was 7.1 months, which the investigators
said  compared to a median  survival of 4.8 months in previous  studies for such
Stage IV gastric cancer patients (a 48% median survival benefit).

     Concurrently,  investigators  from the  University of Nottingham  presented
results  from in vitro and in vivo  pancreatic  cancer cell line  studies,  with
Aphton's G17DT in combination with gemcitabine. In the in vivo study, with tumor
weight as the principal  measure,  the combined benefit was a reduction of tumor
weight of 55%, a statistically significant (p=0.025), 45% benefit over that with
gemcitabine alone. The investigators  concluded:  "Anti-G17DT antibodies provide
an additional  anti-tumour effect over that which can be achieved by gemcitabine
alone in the treatment of pancreatic cancer."

     On Sunday, May 19, 2002,  investigators from the UCLA Jonnson Comprehensive
Cancer Center in Los Angeles,  California  and the MD Anderson  Cancer Center in
Houston,  Texas,  presented further  impressive  interim results from a Phase II
clinical trial with  previously  untreated  patients  diagnosed with  metastatic
stomach cancer. The patients were treated with Aphton's  anti-gastrin  immunogen
(G17DT) and chemotherapy consisting of cisplatin and 5FU.

     Of the 36 reported and audited  evaluable  patients (20% more patients than
previously reported), 19 had a partial tumor response (tumor shrinkage by 50% or
more) for an overall  response  rate of 53%,  the highest yet  reported for this
combination  therapy.  Of the balance,  11 patients had stable  disease (SD), so
that the combined  tumor  response rate and stable  disease was 84%. One patient
had a complete  response  (no  detectable  residual  tumor) and 18 had a partial
response. These results compare favorably with the only large, randomized, Phase
III trial with cisplatin plus 5 FU/Leucovorin for patients with advanced gastric
cancer,  which  reported a tumor  response  rate of 20%.  Aphton's  anti-gastrin
targeted   immunotherapy  adds  a  biological  dimension  to  the  treatment  of
gastrointestinal cancers.

     On Friday,  May 17, 2002, a special  symposium was held by Aventis (AVE), a
major pharmaceutical company and Aphton's strategic partner for treating cancers
with  Aphton's  G17DT.  Jaffer  Ajani,  MD, of the MD Anderson  Cancer Center in
Houston,  Texas and a  leading  authority  worldwide  on  gastrointestinal  (GI)
cancers,  described the molecular  and  biological,  central role of gastrin and
gastrin  receptors in the development,  growth,  proliferation and metastasis of
adenocarcinomas  of the GI  tract.  Noting  that  there is no  approved  therapy
currently  available and that  chemotherapy is considered only  palliative,  Dr.
Ajani  discussed the  inhibition of the growth and spread of these  cancers,  in
vitro, in vivo, and presented the above described audited interim results of the
clinical  trial with patients with  metastatic  stomach  cancer

                                      -2-
<PAGE>

who were treated with Aphton's  G17DT and  chemotherapy  consisting of cisplatin
and 5FU.

     It is estimated that there are approximately  570,000 patients with gastric
cancer in the US, Europe and Japan alone.  The  prognosis  for the  overwhelming
majority of these  patients is very poor.  Patients  diagnosed  with  metastatic
disease have five-year  survival rates of only about three percent.  Surgery and
chemotherapy are the primary  treatment options  currently,  but have shown only
very limited  benefit.  Aphton believes that its  anti-gastrin  approach has the
potential to extend life without adding toxicity to the therapeutic regimen.

     Aphton is  conducting  one Phase III and three  Phase II  clinical  trials.
Aphton's  anti-gastrin targeted therapy induces antibodies in patients that bind
to both gastrin 17 and gly-gastrin and remove them from circulation  before they
can bind to the cancer cell and initiate cell growth.  (Aphton  believes this is
the optimum  method for achieving  "growth factor  inhibition.")  Gastrin 17 and
gly-gastrin  are  believed  to be  central  growth  factors,  or the  initiating
signals, for cell growth, cell proliferation and metastasis (spread) in gastric,
i.e. stomach, pancreatic, esophageal, colorectal and other gastrointestinal (GI)
system cancers. This signaling program is accomplished by gastrin binding to the
large numbers of gastrin  receptors which appear, de novo, in the great majority
of  cases,  on tumor  cell  surfaces  throughout  the  gastrointestinal  system.
Interrupting  this process by immunizing the patient with Aphton's  anti-gastrin
immunogen is a precisely "targeted" immunotherapy. This specificity of targeting
only cancer cells occurs  because  gastrin is not normally  secreted and gastrin
receptors  are not normally  found on "healthy"  cells in the GI system,  unless
they are malignant, or on the path to malignancy (except for cells involved with
normal acid secretion).  Recent findings have shown that inhibiting  gastrin not
only inhibits  cell growth,  proliferation  and  metastasis  directly,  but also
"unblocks" a central pathway leading to cell-suicide (apoptosis). This tilts the
balance,   from  cell  growth,  to  cell  suicide.   This  effect  is  amplified
synergistically  when Aphton's drug is given  together with a  chemotherapeutic.
Gastrin also stimulates the secretion and expression of other  important  growth
factors and receptors within and on the surfaces of the cancer cells involved in
tumor growth.  Hence,  inhibiting  gastrin inhibits all of the foregoing factors
contributing to tumor growth and spread, while simultaneously  opening a central
pathway to cell suicide.  Aphton's  anti-gastrin  targeted  immunotherapy adds a
biological dimension to the treatment of gastrointestinal cancers.

     The Company is a biopharmaceutical company in one Phase III and three Phase
II  clinical  trials  developing  products  using  its  innovative  vaccine-like
technology for neutralizing hormones that participate in gastrointestinal system
and reproductive system cancer and non-cancer  diseases;  and for the prevention
of pregnancy.  The Company has several strategic  alliances  including strategic
alliances with Aventis Pasteur (NYSE:AVE) and GlaxoSmithKline (NYSE:GSK).

ITEM 7.  EXHIBITS.

     (c) Exhibits.

          99.1 Text of Press Release of the Company dated May 20, 2002.

                                      -3-
<PAGE>

                                    SIGNATURE

     Pursuant to the  requirements  of the  Securities and Exchange Act of 1934,
the  registrant  has duly  caused  this report to be signed on its behalf by the
undersigned hereunto duly authorized.

                                         APHTON CORPORATION
                                           (Registrant)

                                         By: /s/   Frederick W. Jacobs
                                            ------------------------------------
                                            Name:   Frederick W. Jacobs
                                            Title:  Vice President, Treasurer
                                                    and Chief Accounting Officer

Dated: May 20, 2002