I have never heard of any contemporary account that directly refutes the gospel story, and it is unlikely that a refutation of the gospels was ever written. Although we can never know, it is unlikely that the pagans were at all concerned, or threatened, by the emergence of what they still regarded as a new strand of Judaism. The Jews were, at that very time, preoccupied with the events of the First Roman-Jewish War and its aftermath, including the loss of the temple, the inability to sacrifice to God, the disbandment of the priesthood, and the future direction of the faith.
Philo of Alexandria, who was an early contemporary of Jesus, wrote about all the Jewish sects and movements that he knew of, but never mentions Jesus. That does not mean the gospels are not historical, just that news of Jesus never reached Philo in Egypt.
Josephus wrote about Jewish history late in the first century, but he seems either unaware of or uninterested in the gospel story. His brief mention of Jesus in the Testimonium Flavianum is clearly second hand and appears to have been heavily redacted by later Christians.
Of course, even if a meaningful refutation had ever been written, we could expect it to have been destroyed along with the pagan and gnostic documents that were burnt during the Christian rampages of the fourth and fifth centuries. Even gnostic Christian books were not spared, with the Nag Hammadi library, sealed and buried in the Egyptian desert to avoid the destruction of these sacred book, as silent testimony to the thoroughness of the sanctioned destruction of literature that did not meet official approval in the fifth century.
Barbara Geller says in 'Epilogue', published in The Oxford History of the Biblical World, page 427, that by the end of the fourth century, both anti-pagan and anti-Jewish legislation would serve as licences for the increasing number of acts of vandalism and violent destruction directed against pagan and Jewish places of worship carried out by Christian mobs, often at the instigation of the local clergy. Helen Ellerbe says in The Dark Side of Christian History, page 46, the Church burnt enormous amounts of literature. She says Christians burnt down the library of Alexandria in 391, with its 700,000 rolls - although the number of scrolls may already have been substantially reduced by early fires dating back to the time of Julius Caesar. The destruction of books was random, with books on science, mathematics and engineering joining those on philosophy and religion. On page 44, Ellerbe says that in some cases the Christian church's burning of books and repression of intellectual pursuit set humanity back as much as two millennia in its scientific understanding.
